hehe that sounds fun when we were at our most on LAN we had 12 players, wired network, my house was stuffed
There have been issues before on wireless internet players, appearently they "teleport" cause your computer searches for a better network every min or sumthin like that, there was a thread about that somewhere on the forum. I myself often play MTA on WLAN to my friend, and he doesn't teleport. But if people complain then this could be the reason just so you know.
As to the lag, umm ping should stay at 5-15 and you will still notice that the netcode isn't perfect, but its runs very smooth.
Have fun with it!
edit: here's the relevant topic if you have Wireless Internet and are experiencing teleporting.
http://forum.mtavc.com/viewtopic.php?t=7017
you have 12 computers? holy fuck, i have 2.