There are two good choices - Tactical Solutions or Weigand.
The TacSol is available with and without a built-in rear sight. I have the one without the rear sight. The Weigand is very similar. These two are very solidly built and will serve you much better than the B-Square. The B-Square is an extruded part, so it ends up being hollow on the underside and tends to work loose.
I have heard from others that the TacSol model with the rear sight requires the use of a taller replacement front sight.
