The FCC has publicly announced they can not enforce any laws pertaining to using anything over 1.5w in FRS and GMRS frequency bands. You can even find "walkie talkies" in Sporting goods stores now that uses higher than normal wattage. I use a Puxing 888 which has been great. Wouxon, Puxing and Yaesu make some great radios. Yaesu is generally very expensive for airsoft. I have had a set or motorollas, cobras and midlands which SUCK IN EVERY WAY in comparison. If you play in large areas, in builds, up and down hills or just want to have a nice radio get a 5w UHF from Puxing or Wouxon. Make sure you can manually program them or with a USB.
UHF, USB cable, digital FM radio.
Dual band UHF/UHF dual channel with extra battery free shipping. Dual band is both VHF and UHF which would allow you to talk to everyone if for some weird reason if someone is in VHF. No body uses VHF but running two UHF channels at once is nice. If you help the admin out and just want to stay in touch its easy to listen/respond to two different channels.
You are going to want to do some reviews and find out what kind of pin these use so you can get a PTT headset and mic. I bought mine from ebaybanned for $30 and it work great. One of the few thing their cheap ACM manufacturer made well. Both of them have a FM radio which is great. I listen to the radio when I play sometimes. When every the channel is mic'ed the radio switches and turns back to FM after the person is done talking.