I've run FFXI on my grandfathered VZW Unlimited Data Plan for around 2 years through PDANet+. If the speed gets throttled or the connection becomes congested, FFXI rarely ever goes down, and is usually the last to go when it does.
In all honesty, It's the most reliable connection I've played on.
Agree here, when you get throttled it doesn't phase ffxi at all (playing) but if you d/c and try to log back in... holy *** its terrible.
My phones connection is considerably more reliable than comcast or att I've used.