Unbelievably slow gameplay. I had to keep the mouse held over the tile for 5 or more seconds while waiting for the click to register.
Tiles were teeny-tiny on my screen, and I couldn't change the view angle. If the tiles will be small, at least present them from above, instead of from the side.
Tiles are nicely presented, so I give a 2 for that. It didn't crash for the brief time I played it, but I think responsiveness is part of stability, so it gets a 2. Features are otherwise what I expect from a mahjong game, so that gets a 3.