There's a reason films like Kodak BW 400CN is so popular--easily developed, very little "grain," and no problems using Digital ICE when scanning.
edit: That said, I still don't believe that any C41 film can fully replace a silver halide emulsion like Tri-X, as it's extremely difficult to pull off push/pull processing with C41 and there are many times I'm stuck at night with B&W films that would be very infeasible to shoot at their box speed.