Empty-headed amusement
PAIN could never sustain its momentum as a full-fledged, shrink-wrapped product, but for a $10 download it's not half bad. It's oddly absorbing for such a shallow exercise, but I'm not sure that many people will appreciate its oddball humor and the impressive virtues of the Havok engine.
In this day and age, where games are expensive and short on content, at least you get what you pay for with PAIN. There's not many options out there for a mere ten bucks, so at least this is a decent diversion, with some potential for expansion.