Not really since you can download a program that unlocks them.
I'd be dubious of using any program in association with my Steam account, purely for the fact that if you do get caught exploiting Valve usually tend to reward you with your account getting perma'd and all your games go along with it

I know what you mean, it's just as easy to go to an unlock server and hax through most of the achievements and then get a few friends to help you on the last one. Not real great learning of the class you are unlocking

shows how much i use the new weapons.