If you are comparing AS with A2 then comparatively A2 is MUCH MUCH tougher than AS. But if you look at A2 alone then it's hard but not extremely hard, if you start preparation early and do sufficient past papers(6 years atleast). If u do last 6 years past papers (all variants) then an A* is almost confirm , provided that you did the past papers with utmost concentration and understanding. Gudluk...