Speed upgrades are listed 250, but cost 100. Shop should state you are buying "300 ammo (will replace current ammo even if same type)".
Spread cannon best primary for mob clear, Laser cannon best boss kill... others are not as good.
Wide Blaster best secondary, Octo and Random are unreliable, Controlled means that since aiming and ship move are the same (mouse) it will cause unintended collisions/death.
Guided missile is great in all situations, other two are boss kill.
Recommend change from Primary Weapon to Primary Ammo to avoid confusion, and likewise the others.
Otherwise this is a MUCH better entry level game than what I'm used to seeing. Also the Boss on level 5 one shots ships, need to fix that, and the score reset on me twice. I got 1209 but should have had 2000-2500. Issue with being idle in the shop (time I spent typing this)
Not very fun, tapping W to pulse engines (rather than hold W) results in unlimited fuel from the beginning, sound and music are bad, upgrading speed begins to make game harder, traveling in one direction causes stars to spawn along sides of window (http://i.imgur.com/JIRBgOm.jpg).
Sorry, but this pretty damn bad.
 "Volve"){kind=icon}
 "Dragon of Ecology"){kind=icon}
 "Space Game"){kind=icon}
 "Idle Mine"){kind=icon}
 "Redshift"){kind=icon}