I have an older Iphone 3GS with data plan but cannot tether wirelessly because ATT/Apple won't allow it even though it is capable to do it. Only bluetooth and USB. I used it with Windows ICS (Internet Connection SHaring). I found the connection very slow and unusable with Remoterig. Downlink was very fast, but uplink was less than 200Kbps. Tests with Verizon were positive, no issues. This was 6 months ago, need to try when I get the new IPhone that will be announced soon.
I also have Netgear WNCE2001 bridge at home and it works flawlessly.