I enjoyed it!
A well presented fun lil' game!
The graphics were very polished and neat, glad that the background changed for the different stages..orange was becoming a bit too much after a while :p
Some of the early levels were fairly challenging in comparison to after the first boss. The first boss was real good, having to juggle between him and the minions that come down from all angles. There is a nice variety of upgrades That explode and look pretty which is nice to see.
After the first boss though the game became a little bit easy because the money rewards ramped up making upgrades real quick and everything just got obliterated from then on. Scaling of difficulty is pretty common though with games that have this style of upgrading..tough to tweak!
I also felt you moved a little to slow even with a full speed upgrade, however it just made the game a bit harder..though in a frustrating type way.
Music wasn't to my taste, a little bland compared to the action going on, on the stage.
However, overall it was a really well presented game that looks nice and plays well - the scaling of difficulty coinciding with upgrades just needs some tweaking!
However