The only place besides the L&L that closed down in Mesa that I have found saimin (haven't been to Happy Valley L&L). Unfortunately, sometimes the broth is WAY too salty (like inedible, makes you sick to your stomach salty) and the filling on their wonton is too "crunchy" when soft in the saimin (Water chestnuts inside? The filling texture is fine when they're fried...)
The fried wonton are tasty and the spam musubi are delicious. They seem to run out of musubi fast some days though. Even with their specials, their menu is very limited, so don't expect anything similar to Rainbow's or even L&L.
When I last came in they had done a refurbish/redecoration on the interior and spruced up the walls. If looks better than what they had before.
Definitely a step above the likes of Ono Hawaiian Barbecue. If only it wasn't so far from me now!