Man, this topic has been throu so many times, look into some old posts, but to save you hassle here it goes:
Any 4wd chassis is ok for drifting, its down to tires. The obvious choice is Tamiya TT01 or TT011D and HPI E10 drift. They are the cheapest but require some hopups such as alu prop shafts and ball bearings (hpi and some versions of tamiya). HPI is RTR - complete with radio, battery and overnight charger, tamiya comes as kit to assemble, no radio and some versions no motor and/or esc (AFAIK). They both are shaft driven.
Next in line are belt chassis as tamiya TA05 or HB Cyclone S - they're more expensive but better quality in return. It's ones personal preference between belt and shaft. I went for Cyclone - came in kit so I could choose motor and esc and I had radio from other model. In my opinion belt offers smoother drift witch I like and there's tonnes of hopups for it on RCMart.com at decent prices and good quality.