• Playability—9/10—The various types of jumps, inertia factors, and design differences in different areas make progressing through this game interesting and challenging.
• Replayability—6/10—The game is fun to replay to a degree and leaves you satisfied after completion. However, replayability after full completion is not present, which is completely fine with a game like this.
• Compatibility—10/10—Full support for the keyboard and controller in the browser allows this game to be played by people of all types.
• "Fun" Factor - 7/10 - OK. Here we go, people. I like this game A LOT. Personally, I loved going through each area and finding out each area's intricacies on the best and best ways of progressing further; however, I HATE the "Arm" area. It made me want to take my computer outside, smash it to tiny bits with a sledgehammer, then melt it with thermite. It's genuinely a mishmash of "Getting Over It" and "VVVVVV" (but only in the arm section). 

Summary:

If you like / love platformers and all the challenges they present, look no further. The interesting twist with inertia is unique and keeps the entire game experience challenging.