Depends how much you want to spend really.
I did mine with a 300 http://www.google.co.uk/products/catalog?hl=en&xhr=t&q=dremel&cp=4&bav=on.2,or.r_gc.r_pw.&biw=1920&bih=934&wrapid=tljp131195530954406&um=1&ie=UTF-8&tbm=shop&cid=11278477512035229182&sa=X&ei=VdkyTvvxO8iy8QPvxOChDg&sqi=2&ved=0CGgQ8wIwAg#