Belt-Drive turntables are really meant for consumers. If you're going to be beat matching or scratching, get direct-drives. The problem with belt-driven is this. They don't hold their pitch - at all, they speed up and slow down throughout the tune (not only during the beat-matching process) and they're effected badly by heat - as the belt stretches and contracts. I must stress though that this doesn't only happen through heat - with belt driven decks it will happen anyway with general use.
Direct Drive turntables use a motor instead of a rubber belt. The Motor os responsible for the spinning of the platter. For DD turns, the torque of the platter directly affects the selling price, that is, the stronger the torque, the more expensive the table.
There is, however, a school of thought that starting off with bad decks will help you in the long run. Here's why:
1) Bad decks that lose their pitch will easily teach you how to be really precise when it comes to beat-matching...
2) They also teach you how to correct timing errors during the mix (coz they go out of time all the time)
So it all comes down to a matter of mind over money. How impatient you are is going to dictate what decks you get. Just remember that after about 6 months, you'll start to feel REALLY limited by these decks, and want to upgrade. Selling your decks second hand will not return half of the money you spent on them, so you'll end up spending a lot more money in the long run.
Belt driven decks are less expensive but will not last as long and offer less flexibility than Direct Drives. If you have the money up front, buy Direct Drive turns.