I enjoyed it, but the deal breakers were 1. The controls were a tad too floaty and 2. Even with upgrades like magnet, and the larger drill, it was still hard to tell waht was and wasn't a gem, requiring lots of grinding. and the magnet's range was so short by the time you saw it wasn't a gem it was too late.
However, the graphics and the way the game functioned in terms of UI was pretty much flawless. It looked great and nothing was annoying or buggy in the menu.