AT&T wireless WAN service: feedback

I've just installed an AT&T Edge GPRS card in my ThinkPad and I'm curious
about others' experiences with this type of service.  

The installation process was normal, meaning the software supplied on the CD
was obsolete and I had to download a newer version.  Then the local (0.4
miles away) tower was down; the T-Mobile network was the only one that
showed up and AT&T doesn't roam on T-Mobile.  Some number of hours later,
the tower experienced spontaneous remission and I was on the air.  

I've since found throughput to vary between 26KB and 100KB.  Browsing is
moderately okay and e-mail works fine; Client Access appears to be okay
also.  CODE, with the totally excellent EVFCTCPD.EXE (it just crashed, even
though I'm not using CODE) running things, is pretty bad; I'm getting
strange messages and more than the usual number of lockups.  I haven't
experimented yet with WDSCi.

I'm thinking that the data transmission over the air might be in "burst"
mode, due to latency and polling issues, and this might be the reason for my
problems.  I was hoping for speeds and reliability in the
"better-than-dialup" range from home and on the road.  So far, I am
underwhelmed.

Has anyone else had a good or bad experience with wireless WAN service?  The
AT&T service offers a 30-day free trial and then an $80/month rate for
unlimited data transfer.  The alternative is a Sprint PCS card.

Regards,
Reeve Fritchman
Ayers Rock Software LLC
4915 S. West Shore Boulevard
Tampa, Florida 33611-3329
(813) 831-8574 (voice)
(813) 832-6391 (fax)