I tried keeping my tank at 97 for a few days (it's difficult as I just have a rheostat and live in a basement so my temps keep changing anyway.) I have to say that Tiamat doesn't seem to like it very warm. She mostly hangs out on the cooler side of the tank and sometimes in her moist hide. Now that I've been maintaining it around 93-94F, she seems to be more content. So maybe it just depends on the gecko. Gregg's geckos have all been raised at 97 so that's what they're used to, maybe?
Oh, and it should be known that my probe is kept in the warm hide. I also occasionally check other areas of the tank to be sure.