There's a major problem w/ Wa sushi on la cienega, and it's that the sushi is just not very fresh and not very good quality. it is a high-class joint, but i don't know why they're shintzing on quality. from toro to yellowtail, it's almost frozen pieces of fish, which is not a good sign and they don't have the right texture, the fish should be cold but not frozen.
on the other hand in general, their cooked dishes are quite good like the praws in a butter wine sauce, the foiegras/chilean sea bass combo in a reduced red wine sauce, and other cooked dishes.
as regards sushi anywhere else beats them hands down, esp. echigo, nozawa, mori, kakemoto.
also, the omakase is really not a good deal, it's almost as expensive as just ordering the dishes off the menu.
if you do go, stick to the cooked dishes and desserts.