I went to Sushisho Masa in Nishi Azabu on my own a few years ago and loved the experience! Went with no referrals, but I had to be seated during the gaijin/out of towners seating from 8:30p.
For info on Sushisho Masa, please check out Portos’s review Tokyo: Sushi Sho Masa. Sushi Perfection
I also went to Sushi Sho in Yotsuya for the reserved lunch, but I thought the experience was just ok. It was a good chirashi sushi set, but it bothered me to see some of the young itamae looked as if they just fell out of bed — one of them forgot to put certain neta/ingredients on the chirashi sushi and when the young non-Japanese customer pointed it out, he was flippant and said he was just joking and plopped some stuff on to the chirashi bowl shrugs 