I ended up getting both the Verizon Wi-Fi Hotspot Service and PDAnet. The Hotspot service is OK -- dead simple to set up and use, but pretty slow. (Around around 275Mbps down, 320Mbps up)
PDAnet was great on a USB connection, but I couldn't get it to work via BT with my laptop or iPad. It was MUCH faster than the Hotspot Service -- 600Mbps down, 520Mbps up.
Although I like "free" better than $20/month for 2GB, I think I'm going to keep the Verizon service through the winter. We've been having tons of power and cable/Internet outages this winter, so it's worth having an extra link.