OK game - quite playable on easy, but nothing stunning: once you get three/four-way bullets its a little boring (and you can get this very early on). Difficulty setting is ridiculous: easy is easy, normal and hard are impossible: once you encounter the first boss you discover he's insane, rushing at you onto your side of the lightning bolt - impossible to dodge as not possible to have collected enough speed (not even sure if I could dodge with maxed speed).
Lightning bolt is a little silly, and it is strange that I'm swimming forward (background scrolling left), so my enemies must be swimming backwards!?!
One annoyance: if I get hit, holding the fire button no longer works (I have to keep tapping it). Bug?
Never had a problem with not getting power-ups or coins - just sometimes too slow to collect them all (need magnet power-up?) Later in the game, spent a lot of time dodging power-ups (makes game feel stupid).
Real challenge is the bonus levels!! (That third fish on bonus level 1 is more luck than skill!!)