I wish we had seen @chandavkl’s report back on Opal before we went, but alas, we had gone before this FTC post was written.
Opened inside the newly built Sheraton Hotel in San Gabriel, Opal tries to set itself apart from most other Chinese restaurants in the San Gabriel Valley on a variety of fronts. First off is the decor, which is definitely better than most standard SGV restaurant decor (with generic drywall and maybe some framed pictures).
Opal bills itself as “sophisticated Cantonese cuisine in its purest form,” so we were excited and interested to see how much better this might be compared to SGV stalwarts like Sea Harbour.
The menu is a hardcover, sturdy, bound book, and every chair had an additional pillow cushion. Unfortunately that’s where the niceties ended.
They had 5 Teas to choose from, with some rather humorous English translations for the descriptions (but perhaps it’s true?). For example, for Pu Er Tea, the menu states “It soothes the liver and moistens the lungs.” 
We chose:
Tie-Guan Yin Tea:
Our server poured the first cup (and never returned), and it looked and tasted clearly like it wasn’t steeped long enough.
Double Boiled Chicken Soup:
This was the best dish of the evening: A deep poultry flavor coming through, clear, light Chicken Broth, and the Chinese Herbs present here imparted a pleasant, delicate, fragrant backnote with each sip. (A good medicinal soup offering @Bookwich)
The terrible service started with this very first dish: After we finished our Soups, our bowls were never cleared away. They just sat at our table until the next dish arrived. And even then, the server who brought the next dish saw our empty Soup bowls and was about to walk away (doing nothing), until we explicitly asked them to please clear away our finished bowls.
Poached Seasonal Vegetables (Supreme Broth, Crab Meat):
This looked a bit messy and chaotic, but there might not be a lot they can do given the dish. The actual Pea Tendrils were tender, and cooked through, but it really didn’t taste any better than Poached Pea Tendrils we’ve had at other noteworthy SGV restaurants. The Crab Meat and Goji Berries were a nice touch, but overall flavor? It was about the same, really.
Live Spot Prawns - Boiled:
One of our favorite Hong Kong / Cantonese dishes, Opal was serving Live Spot Prawns, Boiled on the menu this evening. Presentation is nicer than usual, the use of some Flowers and Micro Herbs to try and set the dish apart (not sure if those Flowers are edible though).
The Spot Prawns were undeniably fresh, and properly cooked. Unfortunately the Soy Sauce-based Dipping Sauce that usually accompanies this dish was far worse than Sea Harbour. 
Just a very one note, generic Soy Sauce flavor that actually detracted from the Spot Prawns. Very disappointing.
Signature Peking Duck (Organic Duck from Grimaud Farms. Roasted and Air Dried in Our Special Duck Oven) (24 Hour Advance Order):
We clearly knew it was suspect ordering Peking Duck from a Cantonese restaurant, but given what the manager told our Chinese-speaking friends (who made the reservation for all of us), and what the menu stated prominently - they even claim to have a “Special Duck Oven” - Opal’s Peking Duck was apparently the star of the menu and a “must order.”
Taking a bite…
It was OK. The Peking Duck itself was lukewarm. The Duck Skin (the most prized part) was slightly crisped (respectable), but the interplay of the Duck Skin, Duck Meat (both lukewarm / cold) with a bit of the Hoisin Sauce, Cucumber and Green Onions imparted a rather average result. 
While it’s been a few years, it is not a hyperbole to say that our last visit to Duck House yielded a much better Peking Duck experience and taste than Opal (@chandavkl @PorkyBelly @strongoxman @beefnoguy and others). And at $75 (+ tax & tip) for this Peking Duck, it didn’t feel like it was any better (and rather worse) than Duck House’s version.
We ordered one other dish and it never came out (even after waiting for over 45 minutes and asking about it). In the end we cancelled it.
Osmanthus Jello:
Probably the best plated dish of the evening, this showed some of the plating potential for Opal (in trying to be elevated Chinese cuisine). The actual Osmanthus Jello was lightly sweet, chilled with little bursts of piquant from the Goji Berries. It was fine.
While the above meal wasn’t “horrible,” besides the Double Boiled Chicken Soup, the rest of the dishes were just on the good, but not great side of things. Ingredients tasted fresh, but actual flavor and execution were as @chandavkl noted, merely good, but not mind-blowing. Certainly not elevated above SGV’s best to justify its markup in prices.
But the most egregious flaw to Opal is in its Service. Opal ranked as the #1 worst service we experienced in 2018. It took me this long to write about it because of how horrendous it was. It’s even more standout in how bad it is because of what Opal tries to bill itself as (from the menu) “changing the landscape of the restaurant offerings in San Gabriel.”
After our server took our order and poured the 1st cup of Tea, she literally disappeared. Never to return even once. 
None of our dishes were ever cleared until the next dish arrived, if we had messy plates (e.g., shells from the Live Spot Prawns) after finishing up, it just sat in front of us, and no one came around to clear them out and give us new plates.
Our Hot Tea (Opal upsells you to their “Premium Teas”) were never refilled without us explicitly trying to flag down a server (not ours, because she disappeared and never came back). In one instance, we were out of Tie Guan Yin Tea and tried to get the attention of any server for about 5 - 6 minutes. It was laughable and sad. (Our friend joked, Opal should’ve installed the Doorbells that are on every table at most Korean restaurants in K-Town, because at least someone would realize we needed some help.)
And it wasn’t just our table either. Here’s a picture of another table that finished eating, and their table filled with dirty plates, sat uncleaned for the entire time we were dining(!). As other diners finished up, we noticed not a single table was bussed, and by the time we left, there were like 4 - 5 tables filled with dirty plates and dishes, which made Opal seem like a joke of an effort to be “high class.” 
Pic:
When one of our friends got up to use the restroom and put her napkin on the edge of the chair, it wasn’t balanced and accidentally fell on the floor, right in front of one of the main “walkways” between tables in the restaurant (i.e., very obvious in the main walk area). We saw 4 different servers walk right past it (and one walked on top of my friend’s cloth napkin, and no one picked it up or noticed it). 
It’s one thing if we were dining in a casual SGV Chinese restaurant and we had issues like this. But when even when a basic hole-in-the-wall like Sam Woo BBQ has much better service (you better believe dirty dishes and tables are bussed within seconds of a table leaving, and they’ve swapped out plates for us, and refilled our Hot Tea Pot numerous times, sometimes without asking), you’ve got problems.
When we brought up that they forgot a dish of ours and that we never saw our server again, they offered no apologies and just kinda nodded, before bringing out the check (with no adjustment).
In the end, Opal Chinese Cuisine fails to deliver in redefining anything with Cantonese Cuisine in the San Gabriel Valley except its decor (which isn’t even as good as the visual stunner that is Bistro Na’s). The Double Boiled Chicken Soup was pretty tasty, but everything else ranged from OK to good, at best. Add in the horrendous service issues and unbussed tables and it was more uncomfortable eating here than most hole-in-the-walls in the SGV.
Opal Chinese Cuisine
(inside the Sheraton Hotel)
303 E. Valley Blvd.
San Gabriel, CA 91776
Tel: (626) 607-2018