Lured By the Dark Side - Update
Sorry about not posting this update sooner. I was reminded today by somebody who e-mailed me asking how the replacements turned out.
The short version is that there aren't any replacements. When I called CafePress in late December to arrange to return the shirts they told me that the quality wouldn't get any better unless I changed the shirt designs. The only other option offered was to refund my money - an offer I accepted.
I was so depressed by this turn of events that I didn't even bother to try returning the Zazzle shirts.
So basically this process is not ready for paying customers yet, unless you have a not-so-colorful design that would benefit from the "distressed" look they are now touting on CafePress.