2 things... first, if you're only going to be using the t610 with the t616 antenna in the USA, then it won't matter at all because the phone will never be on 900mhz or 850mhz. It'll just stay on 1900mhz, which both antennas are already tuned for.
secondly, i think that the person doesn't quite know what he's talking about in relation to these phones. I think this for two reasons. First of all, the T610 antenna is R1A, and the T616 antenna is R2A. This leads me to believe that all it is is a newer revision of the antenna hardware. Also, the fact that the antenna must work with THREE different bands means that it's probably a bit flexible with signal
