I push my Trek 1000 pretty hard and find the Sora components do fine. I sometimes need to half click the front derailer (left brake lever) and pop the button when crossing the 1/2 way on the rear gears. I understand that this is normal for other component levels as well.

For the convenience of gears you can change using the brake levers, I reckon it is worth getting them. Soras have been just fine for my riding - I even blew my 2 mates on Colnagos (with all the bells and whistles) this last week, so it isn't all just about the bike !