Gunsaw has high replayability through challenge potential, since not everything is required to beat a level. Yet the lack of updates is probably going to kill it off, since even with all that replayability, a game without updates will eventually die out, regardless of how far developed it is.
It feels like this game is going to be completely abandoned by Orsoniks, and I don't take that as a good sign for the potential of other games by this creator...