Lotsa great modules out there.
Mo Phatt
Triton
XV2020, 5050, 5080
(I kind of even like the Proteus modules - 2000 for sure)
Motif
blah blah blah, list goes on.
Depends on what sounds you're looking for (specifically, not just genre 'hip hop" but *which* hip hop sounds you're looking for)
Another 2 centz I could hand out - Akai's dropping U.S. distribution, so if you pick up an MPC, expect *no* support for your gear. I would take a long hard look at the *why* you're purchasing it so as to be absolutely sure you're buying it because you have to use it for production, or because someone told you to, or "everybody's using it". If it's what you have to have, then more power to you.
You could actually have a backup plan with a Yamaha motif (keyboard) so as to have sequencing/sampling capabilities, and you could drop the MPC all together. Motif reads akai format samples.
Or do the computer thing... (or not). That's always a scary road. But lotsa people do it.
Lots of options, and lots of homework for you to do.
Bang for the buck in my opinion under 1,000 -
Roland XV5050 or Motif Rack.
Have a great one, and remember - all this information is worth my 2 pentz.
-muzakal
