I've just ordered a set of the three door variant for the GTA, so will feedback if they're any good or nor. Ten day delivery time though, so will need to be a little patient!
Had ten days in the Florida sunshine and these were waiting when I got back, so had a go at fitting them with mixed results. The pack includes identical single-piece nearside and offside rear window shades, with the rear windscreen divided into two parts of identical size, and then four clips. Essentially, you position the shades as required and the clip then slots behind a piece of the existing trim to secure.
Only, it's a bit of a mixed bag. Oddly, the nearside rear window single piece fits snugly with no movement, yet the offside piece does not. It fits, it just has around 10mm more play than the NS, and even swapping the pieces around (they're interchangeable rather than being designed specifically for one side or the other) makes no difference.
The rear screen is even odder. Fitting the NS half is no bother, but the OS simply doesn't fit.
I've had to wedge it in place slightly askew, and as above, even attempting to swap the shades left to right makes no difference.
This leads to the conclusion that my GTA, for whatever reason, has a slightly larger window space for offside rear passengers to enjoy, and that the rear screen isn't exactly symmetrical. On the hwole, the shades look alright - though obviously not as nice as professionally applied film tint or factory fit privacy glass - but the fitting issues do annoy. I'll try and get some pictures up to clarify.