I spent a hell of a lot more time with this game than I had expected to when I started playing. I probably played for about 45 mins, but that might be due to the fact that I was also listening to a podcast at the same time. The upgrades seem effective, and the cash doesn't come in too slowly. Also, it's nice that you can just hit "restart" without going into a long winded "what you won" screen before immediately restarting.
The graphics aren't too hot, and there isn't much going on as far as a "story" or anything... My main complaint would be (and this is nit-picky), is that you should make the colors in the upgrade screen a little more bold so you can clearly see what you can afford. Everything is so dark that it took me a bit to realize that I had the ability to buy something that I thought was "darkened" to signify I didn't have enough cash.
Decent game though. Solid 3/5.
Good luck with any future projects.