If you're still thinking about it (which you probably are) I'd say go with something a little better.
Take it from me, I've owned my fair share of crappy plastic guns, plus I'm pretty much in the same spot that you are. I've gone from an $8 pistol (broke), to a $25 plastic LPEG (broke), a Walmart A-17 M4 (almost there... my brother's now) and I currently have a JG M4 and a Kraken AK. (Good guns by the way)
Now, if you're absolutely sure you are only going to play maybe twice a month, then maybe a cheap-ish gun doesn't seem like a bad idea. However, the cheapness starts to seem like a bad idea once you use it in-game.
A springer pistol is extremely hard to use, you will just be handing out kills. Combine that with a crappy hop-up unit (or sometimes none at all), you've got yourself an authentic waste of money. Plus, chances are the part that houses the spring will crack when used enough.
So you're probably thinking - "might as well get a cheap AEG then..." - however, it's the same thing. The gears will break, the batteries will often run out quickly, and BB's will get jammed quite easily.
Since the point of airsoft is to be the last one standing, you're going to want a gun that will last as long as you do. If you don't really want to play that much, so be it - a shotgun or Co2 pistol may be the best gun. However, if you decide to get into airsoft, you might want to get a good starter AEG, that way you'll still have that $100 in your wallet to invest.
It's all up to you, but trust me - you won't be disappointed with a nice gun.