I visited Theme Park Connection last week and thought it was a mixed bag.
They've got some very unique, cool stuff in there (Monsters Inc. ride vehicle, some of those big digitally-printed drop cloths they put over the buildings during refurbs, an EPCOT solar bench...) but a lot of it seemed like overpriced junk. Very little in the way of surplus T-shirts or merchandise, but they had a couple cast member uniform shirts (Universe of Energy, I think) which were expensive, and several miscellaneous cast member shorts and pants which were reasonably cheap. Lots and lots of interesting posters, both framed and unframed, including a lot of internal company posters and postings. They even had some big retirement poster for a cook that I suppose all of his coworkers had signed in the bins with the rest of it. They had a lot of interesting pins for sale for $3 and big bins of cast member name tags roughly sorted alphabetically. Actual in-park stuff (mostly signs) was ludicrously expensive, though they did have a huge stack of dishes and cups that were supposedly used at the Polynesian- I don't remember any Disney resort using anything but plain white plates, and these were cream with a brown tropical-looking print. They also had used bedspreads from Pop or Animal Kingdom Lodge or something (gross!)
I'm sure I'm forgetting a dozen things that might be interesting to browse, but let me make one thing clear- getting to the store, no matter the time of day, is a lot of trouble. Don't just go by the time-to-drive on your GPS; traffic in the area, especially on Orange Blossom Trail and Sand Lake road is murder, and we were there at 6 one night (store closes at 5, btw) and around noon another day and both times it was a tremendous hassle to get to and from that area and back to WDW Property or even I-Drive.
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