I was planning to go, but now that I have to go to Anime Expo (KLK Special Event requires my presence), I'm debating whether I still want to. I already bought the ticket, but it's an easy sunk cost.
I've been several times before, and
in general, you're not likely to find prices much different than you'll find online on US-based importer sites like HobbyFan, BUT you can find older or rare figures that are either exorbitantly expensive or completely sold out online.
For example, back in 2010, I bought a Sheryl Nome
figure at AnimeExpo for cheaper than it was available online at the time, or for a few years afterwards. I also picked up
Tomoe at Fanime a couple years ago for $40, which was at least half the online going price at the time.
Sometimes the sellers are willing to negotiate on price too. I was able to knock $50 off the price of
Solange at Fanime.
As always, keep an eye out for bootlegs. I haven't been bit, but I always hear about at least 1 dealer selling bootlegs either knowingly or not at any convention.