I had a Gretsch bass from the late 90s, just before the current "Electromatic" series came out. My bass self-destructed and I ended up parting it out, to resurrect my Hofner. I can confirm that the pups DO sound great. I can also tell you that they seem identical to the cheap "Firebird style" mini humbuckers on the Bay. I haven't actually swapped the 2 onto the same bass, but the size, wire colors, stickers on the pup bottoms, etc. were all exactly the same. I got a mini from GFS, a pair of minis off Ebay (for less than half of what the single from GFS was) and now a set of minis with 4 polepieces, all on my HOndo Jazz project, and they all sound pretty much the same.
I do have a pair of the chrome pup rings if anyone wants them, for whatever the shipping costs.