Tia, over time the creases should press out for the most part. You might see something that looks like wear lines, but it won't be a problem.
Now days you can search ebay for Teflon Sheets and find them pretty cheap. I found them for $6.00 each. Several years ago I spent $20.
Congratulations on both presses. I want a hat press really bad if you know what I mean, and I'm sure you do.
Stahls Hotronix presses are great. We had a Knight, an generic, and a Stahls, and the Stahls works the best. The only thing is the amount of time it takes to heat up, which I'm willing to live with.
Paul