I am able to do PIN - PIN messaging (i typed in the wrong PIN).
As for latency, geographically the user in question is closer to BES than I am (i'm in Vancovuer, BES is in Toronto, User is in Atlanta). Their latency from GroupWise to BES is also better than mine. To be sure, I'm going to find another US user with a BB and test with his account as well.
Thanks for the Info