Tethering phone to Laptop as a modem - how fast?

[natv]

Hi guys,

I'm still undecided between the HTC G1 (T-Mobile) and the HTC Touch Pro (AT&T). Heavily leaning towards the Touch Pro... but anyway here is my question...

I see that both phones can be used as a modem and tether via USB to a laptop so the laptop can connect to the Internet.

Right now I have a Verizon Broadband Express Card (like PCI but Express port). I'm no longer in a contract and considering just using one of the above phones to provide my laptop Internet when I travel.

AT&T limits the data to 5GB/month I believe, but that is fine as I checked my stats with Verizon and the most I've ever used in one month is 3GB.


But the question is this... what kind of speeds can I expect through a tethered connection?

If the network is 3G, can I expect 3G-like speeds, or does using the phone as a modem cause a bottleneck and really slow things up?

I asked a guy at T-Mobile (regarding the G1 phone) and he said that it slows things down to almost dial-up speeds.

Anyone have any feedback about this?

I'd still have to pay AT&T for the data plan that allows tethering, so it's only be saving $30-$30/month by canceling my Verizon broadband data card service.


Thanks
Nat