I come out of the 15" JBL school, too..but I have mostly converted.
The Uber-bass cabs have the reputation of being pretty awesome, but I haven't played either.
Both are rated 42-18K HZ, and both are pretty sensitive, at 101 and 102 dB 1W/1M. The Uber is 10 pounds heavier, 63 lbs to 53 lbs.
I only have the single 12T Shuttle cab, and it's pretty solid as well. But both the NEO and Uber cabs are generously ported, and they should sound fuller than a non-ported cab.
You may just have to find some and play them.