If you can afford the Puxing PX-888K, it is a good radio for airsoft/MILSIM use. If you are on a tight budget, Baofeng makes a 16 channel programmable UHF radio, that is $22 USD, the BF-888S (wonder if they are playing to the Puxing's popularity?) Cheaper than FRS/GMRS bubble pack radios (two would only set you back $44).
The BF-888S is a basic 400-470 MHz radio. No buttons on the front, so it has to be programmed from a computer. It only has the on/off/volume knob and channel knob. It comes with what is labeled a high gain antenna, although I have no way to test that. It accepts Kenwood two pin accessories, so you can use Z tactical headsets and the like.
The speaker in the radio has a somewhat raw digital sound, like a lower quality mp3. You can hear clearly with it, but when compared to a Wouxun, it doesn't quite have the same quality. It works and sounds well with headset.
A programming cable will run you an extra $10 and so will a spare battery. The one that I have was purchased as a gift for a team-mate's son, so I don't know how long the battery lasts, but it is rated at 3.7v 1500 MAh. (Puxing and Wouxun batteries are 7.4v)
Although it is rated for 4 watts UHF, I am getting just over 2 watts of output on the meter.
So for $22 USD shipped, it is a good option if you can't afford a more full featured radio.