Poebot:
Keep in mind that going the MSA Sordin route is a classic "If you give a mouse a cookie" problem. Once you buy the headset, you'll need the PTT ($100 for the Icom version), then you'll need an Icom radio to plug this contraption into ($100-150 depending on the version, most folks who go this route seem to gravitate toward the IC-F21, but the IC-F4001 is NIB for the same price range), and once you get the radio, you'll need the programming cable and programming software to program it to use the FRS/GMRS frequencies that 99% of folks on AP use (or someone to program the radio for you). Then you'll want a radio pouch to put this in, but you'll realize that the Icom radios have their mic/speaker jack on the side, not on top, so the stupid cable won't come out of the radio at the right angle and you'll end up either cutting the pouch or just jamming the whole contraption into the pouch. $500 later, you'll have a useful radio setup (you can probably save about $100-150 off this by shopping wisely, but I'm generalizing to make a point). Then once you've done all this, you'll realize the stupid antenna is poking you in the stupid face and spend another $60 getting the TCI remote antenna kit (go with the V2 with the straight QC and an Icom AD-98FSC to escape the MX antenna connector problem).
My luck with getting the MSA Sordin Icom PTT to work with the Midland radios is nil, so I wouldn't recommend this route as a way to save money on the setup.
As for the knockoff Peltor/Sordin headsets, mine seems to work reasonably well save one annoying feature: turning the headset on and off involves a loud tone. They interface with my Icom radios and I've had more problems with the radio than I've had with the headset. That being said, you can't cheat and buy the knockoff PTT to use with the real MSA Sordin headset, as the pinouts appear to be different.
Are you buying the headset to complete an impression, or are you buying the headset to own a MSA Sordin headset? Is there airsoft gear you would be better off spending the $60 to buy a cheap FRS/GMRS and spending the other $400 or so on?
As for being "cool", meh. I see a lot of players running around with nothing more than PC with some magazines and an M4 replica who let other idiots play with the radios and seem to be doing alright.
EDIT: because I've gotten at least one PM about using the TCI MAST kit with the Icom IC-F21, you need:
Icom AD-98FSC (
http://www.gmrsoutlet.com/product.php?productid=42&cat=0&page=1)
Antenex EXC450TN (
http://www.wpsantennas.com/exc450tn-antenexcenturion450-470mhztncmaletufduckantenna.aspx)
TCI MAST v2 (Straight or QD, personal preference) (
http://www.tacticalcommandstore.com/tci_mast_modular_antenna_system-tactical_antenna_relocation_kit.aspx)
Total package is about $115, I've seen no constructive difference been the generic AD-98FSC and the Icom AD-98FSC.
The only reason for the AD-98FSC is because some idiot at Icom decided that an MX connector made way more sense than a BNC or TNC connector.