We've been twice. It's, IMHO, one of the best restaurants in WDW and definitely, IMHO, the best in EP. Of the dishes we've tried, the Nikomi Wagyu has been the biggest hit - it's quite large, actually and could definitely serve as an entree (last time we went, my DS12 had a maki roll and the Nikomi Wagyu and it was a ton of food). I had the Sea Bass last time which was very good. I would probably avoid the sushi and sashimi. While the presentation was lovely, I still prefer the sushi/sashimi at Kimono's. The next time we go, I'm going to try the Tempura Ebi which looked amazing!
We did the omakase the first time we went and though DS loved it, it was too much beef for me. IMHO, if you'd like to go, but keep the pricing down a bit, I would highly recommend pairing the short rib appetizer with another appetizer or one of the maki sushi (which are also pretty large portions and can be shared). If we go again as a party of two, we'll probably do an appetizer, a maki roll and the ebi tempura and just share everything.
The staff are really lovely there and the restaurant is beautiful.
Edited to add: to keep costs down, I would also consider getting dessert somewhere else in EP (from a kiosk or the bakery in France). We tried the water cake on our first visit and I did not like it at all. Quite honestly, on our second visit, after having some of DS's maki and my sea bass, I didn't have room for. dessert anyway!