O Shima Japanese Cuisine is at 1448A 17th Ave SW, 403-457-5577. This is indeed the new Japanese place that has replaced the former Mt Everest's. It also makes for a lot of sushi/Japanese in what was once a dead zone for that cuisine, in the west Beltline... we now have O Shima, Oishii Village, Japanese Noodle House, Uptown Sushi and of course Midori which has been around forever. So things are getting pretty crowded, but I've been to this place twice now (twice in the last two weeks; it opened for business on Feb 12) and like it, so I hope it doesn't get lost in the white noise of some pretty average Japanese around.
The menu comprises some predictable items and some not; I've stuck with my preferred tried and true (pork gyoza, spicy tuna/yam tempura/avocado rolls, and unagi nigiri) and have been very pleased with all them. Rolls are not too doughy (vs the clods of rice I used to get at JNH, one reason I don't go there anymore), tight and presentable; nothing earth-shattering but the chef knows his stuff and doesn't use the medium-grain "cheater" sushi rice you see sometimes (like at Midori). Two nice things: spicy tuna is freaking SPICY but fresh and clean-tasting, no mayo to hide behind, and yam tempura (again unlike Midori, which I really don't hate, I swear) is fully cooked with nice soft veg. Not as good as Uptown but quite nice. Gyoza are among the better I've had in Calgary and a pleasant suprise. I'll add in general that value is very good- $17 for my a la carte lunch (combo specials much cheaper but I never order those) was really too much food, a nice thing to see at a sushi place for less than $20.
Now I have a lot of the menu to explore but let me note a couple of nice things: One is that this place serves ramen alongside the expected soba and udon. I like that as ramen is still too thin on the ground in this city. Second, the "special" rolls comprise some surprises, like the "yellow knight" with spicy tuna, tempura flake, cucumber, green onion inside; outside: uni, avocado, jalapeno, tobiko. This sounds too busy for me (and uni?), but interesting too.
10% off on dine-in until end of March, and they have a facebook fan page (search O Shima or if you're my buddy look for listing under my info) with pics.