Really addictive gameplay.
I thought the combination of graphics and gameplay was fun. I thought the weapons where good, but the pricing compared to how much you can save up to the amount of zombies, is very unfair. I thought it would have been a good idea to implement some sort of multiplier for points from kills, which would increase with the difficulty/amount of zombies. I also thought the pistol was off, as it would take 7-10 shots to kill a zombie when other games take 3-5 shots for a basic zombie kill.
The pay for extras bit is the only downer, as i could not get into this game enough to sanction spending real money for game play; I there was other gamplay modes, like co-op, multiplayer or diffrent unlockable levels, maybe a choice of music and diffrent gameplay modifiers, then it maybe be worth paying to be playing. As mentioned above, yolu state it is to test a new system? I have combed through newgrounds for pay2play games and apart from a few, there aint many. Mainly because most people which submit material on newgrounds, iver do it for free; for other people to enjoy there media/games. or people get sponsored to do it; usally for free gameplay purposes. But because of the quality of the gameplay i cant mark it down, but because the overall quality of the gamaplay, it also makes it not worth while to purchase extras.