well, me not knowing much about cars, I'd say if my brakes worked fine before someone did some work on them and then they felt "funny" then 'something' cant have been done right......surely he tested them after fitting them and would have noticed something was "funny" when he road tested it?

or its a 1 in a million coincidence.....

make sure you let us know whats wrong when you find out though....and dont drive it fast until you find out!