Broken Cingular Prepaid Card (January 3, 2006)

Has anyone else tried Cingular Prepaid and had as bad of luck as me? I thought I would set up my cell phone infrastructure as:

A prepaid card it Switzerland. This is what I normally use, but European cell phones are so expensive (15+ cents/minute) that I won't use it very much.
A prepaid card in the US. I occasionally visit the homeland for a week or so, but not frequently enough that it is worth purchasing a plan.

I tried a Cingular card for the second item, but most of the time people are unable to call me. Even when a connection gets through, it fades out a lot of time. I'd rather have it than not, just for emergencies, but it is useless as a way for people to call me.

In their defense, Cingular's customer support did answer quickly and appear to make a valiant effort to fix the problem. However, it's over a week later now and there has been no progress.

I'm left wondering if there is any good prepaid SIM card for people in southeastern U.S.? T-Mobile doesn't cover South Carolina, so it is no good for me. Even Cingular, which covers the areas I need, has a weirdo plan where prepaid money drains out after a month or three if you don't use it fast enough.

I hope a new offering comes out in the next few months, or I'll end up getting stuck with a plan after all. I don't want to go back to life without a cell phone!