Queen Gambit refused - Qxc3 or bxc3?

Hello,

As a Queen Gambit player I'm often facing a bishop coming in b4 to pin my knight in c3.

As a response I like to play the aggressive Qb3. Now my question is the following: after Bxc3 engines prefear Qxc3 but my personnal feeling is to take with bxc3 and have an open column b to put pressure on. What is your opinion on it?

bxc3 would also give white a stronger center after a c4xd5 exchange as well.

The file would only be half-open, what's more it's only open at your side and behind you. It's almost the same as if the b-pawn were there. The whole point of Qb3 or Qc2 in that position is to capture the bishop with it and not to damage the structure of the pawns. You can't justify that queen's position at b3, especially with how dxc4 and b5 are coming. 

When I played d4 I liked to take with the b pawn. Then play Bb2 and use the Botvinnik plan (f3, e4).  Now, with the bishop already gone, probably the queen is better, specially if after cxd5 he recaptures with the e pawn. Then you do a minority attack.