At $15 for lunch AYCE, 520's prices are fairly standard for the average AYCE sushi establishment.
I visited with a fairly large group during weekday lunch hours and the restaurant was pretty busy. However, this didn't stop orders from being fulfilled in a timely fashion. For the most part, orders came out in good time. I especially liked the fact that iPads were utilized to facilitate the ordering process, and this really maximized wait staff efficiency.
The menu options were standard for AYCE sushi for the most part - nothing that really stood out. If I were to pick my favourite dish, it would have to be the fried salmon belly - this was delicious.
Their actual maki rolls were nothing to write home about - not better nor worse than the typical AYCE sushi place.
Overall, this is a solid place to go for a good meal. There's nothing special about this place though - no wow factor, so don't go expecting the world.