- Problems are all "real life" in the sense of looking like normal game positions. The device of having your "opponent" (the server) make its move before you helps underline this impression.
- The wide range of different problem types also assists in providing an over-the-board type challenge to the player. They range from simple recaptures to material gain to checkmate, so you need to actively figure out what the position requires, rather than programming your brain for a single type of solution.
- Statistics and records are useful when revisiting failed problems.
- The timed rating feature encourages quick moves without checking multiple lines, in a very Pavlovian fashion.
- The rating change indicator for each problem appears to be incorrect, as a ratings penalty always seems to be assessed if the solution is not found in the first few seconds.
- Alternate solutions are not recognized. This affects only a small minority of problems, but is still occasionally annoying.