My advise would be to try some cheap stuff....if its rubbish you wont use it again but you wont be too much out of pocket.
I agree, price is not a good indicator of quality. I have a £15 Nu-tool cordless drill which has done surprisingly well - Ive drilled lots of 10mm holes through 3mm thick steel and cut a few 20mm holes out of the same with a holesaw.

Ive also got a Bosch 240v drill and angle grinder, a friend of mine who worked as a construction planner on the City of Manchester stadium recommended them and they are good tools. Ive used one of the £40 pillar drills for about 18 months now and its still going strong. Of course Ive only recently got a garage with an electricity supply - I built most of my current robot just with the cordless drill and a hacksaw.