I haven't built a lot of Shermans, but I recently finished Tamiya's M4 Sherman (early production version). It's one of the newer Tamiya kits, having been released in the last 2-3 years. I was very pleased with the assembly and the detail on the parts. A good quality kit. The kit gives you a few in-the-box options - choice of different styles of road wheels, drive spockets, etc. Their one-piece tracks have improved as you can glue them together with regular model cement and they look good enough you don't have to worry so much about hiding the place where you glued the track together.
I built the older Tamiya kit M4A3 Sherman 7-8 years ago and the newer kit is a large improvement over the old one. More detail, etc.