Sorry for the low score, but...I have to agree with what Zerodius said about the game...it does start off fun but then the difficulty ramps up VERY quickly and you spend everything on repairing your base and you can never afford the more powerful weapons; and it does suck that you can only keep your winnings only if you win the wave.
Also, one thing that I would either eliminate or GREATLY decrease the durability of in the game is the shields that the skateboard soldiers use. I mean I get the fact that they should be a little harder to kill then the un-shielded soldiers but to have just one or two completely take out your base while you shoot a million rounds into them and they're still standing?!?!?
I know they stop and raise their shields every so often but if you're just a millisecond off on the trigger you lose the possible one shot kill and when your being mobbed you really can't take the time to aim your shots with such a minute window.
Also I had a boss...at least I think it was a boss that had a steel helmet on and he was the same as the shield guys taking shot after shot--headshots even--and never died and blew up as he hit my base almost killing me...you really need to take out or GREATLY reduce the frequency/durability of these kind of nearly invincible enemies.
Bottom line: Make the either the guns or base repair cheaper, give more money for every kill and take out the invincible enemies.