Wireless Laptop Connection

I am trying to find out what the best solution is for wireless internet connection for a laptop. Is there one that is faster than another (Sprint wireless card vs. Verizon wireless card), which one is more reliable or is there another means? Currently my CFO uses a Verizon TREO with Bluetooth to connect to the internet, but it disconnects alot. I suggested Verizon Wireless card, but now he isn't sure he wants it because it may not be the fastest thing going. Any help would be greatly appreciated.

Conrad