I have used the tracks on the Trumpeter IS-3M to give a more realistic sag (although I think they would be more accurate on the KV series up to early production IS-3).
The links are OK but required a bit more work than expected. There was flash to be removed apart from sanding off the excess plastic after the mold plugs were cut off.
Since the molds were a wee bit misaligned during molding, the holes for the track pins aren't perfect. You may need to re-bore the holes to allow the pins a better fit.
The good part is that there are more than enough spare track pins to make up for anything eaten by the carpet monster.
Nevertheless, they are separate links, they look good when finally installed, and I suggest leaving off the fenders to make them visible on the finished kit.