As per my knowledge there are 3 wireless BroadBand (USB Sticks) providers
1. WorldCall - Wireless Broadband
2. PTCL - EVDO
3. Wateen - Wimax
I have used EVDO of PTCL and Wateen, not used the worldcall but have info
that WorldCall is actually not a Broadband but they call it broadband.
PTCL - EVDO is good, it usually give speed from 100 kbs to 400 kbs.
Wateen is excellent it gives 300 to 1000 kbs, WATEEN IS EXCELLENT
On average it give 3 to 4 times faster speed than the EVDO.