I hope $400 isn't your entire budget. You'll need at least another $150 for goggles and boots (yes, you NEED a good pair of boots). As well as batteries, a charger, BDU's, etc. The batteries and chargers that come with low end guns are generally of low quality and should be replaced. I've seen those chargers fry batteries.
The generally accepted number for getting into airsoft is about $1,000. You can comfortably do it on about $600 though, if you pick up a used gun and gear and forgo things like a good tac vest (which is nice, but not necessary at first).
Honestly, a low budget and "good starter gun" don't go together. Cheap guns are generally NOT good starter guns. They don't perform that great, and they tend to break more often. If that's Ok with you, fine... just realise a broxa is a lot more likely to snap something in your first season of playing than a higher end brand.
Oh, and +1 to Sha do.
"Someone in a Prius tried to race me at a stop sign the other day. I couldn't believe it. I had him for the first 100 feet or so but I can only walk so fast."