Get a wide variety of pads.
It doesn't make sence to get a PC and scrimp on the pads, as you're limiting what the machine will be able to do.
Get something like the
Sonus SFX polisher kit from Autopia ($199). That includes the three Sonus 6" pads. FWIW I'm also very pleased with the
Sonus Paintwork Cleanser that comes with this pack.
Then add a 3.5" backing plate and get some 4" pads for spot repair.
I've only had my PC for one evening (it arrived yesterday) and I do not regret buying extra pads - believe me!
Hope this helps.