USD has a lot of good going for it (despite the mysterious and unsupported comment above that it has lost ground recently...
If you want to practice out west, USD is one of the best programs (on par with Loyola in LA, and both are ahead of Denver). If you want to go elsewhere, the reputation does not carry as much weight. I don't mean to say it is worthless, it's just not as well-known in the east as it is in the west (much the same way that Miami and Boston carry more weight in the south and east, respectively).
As far as the program itself, it has a lot of resources available for students in the form of clinics, externships, and networking contacts. USD LLM grads wind up with tax court clerkships and biglaw position pretty frequently. In fact, many of the former tax court judges have strong ties to USD. If you are more into the accounting firm thing... USD gets more accounting firm interviews than any other west coast program... and those frequently wind up away from the west coast.
You're right that its not quite to the level of NYU/Gtown/Fla (or at least what Fla was a few years ago), but it's a good program and worth considering... though if you know you want to go east you should look east (BU, Miami, Nova, Nwestern)