[Perfectlap]

The GT3 is the same frame as the pole position, they just change the design for the top half.
The seat height is about an inch and a half lower than the stock seat in the lowest position. If you add the Brey Krause mount you can lower it a bit more. However as you know the seats are fixed so you won't be able to turn your upper torso like when you're parallel parking and need to swivel. And if your core is not in good shape getting in and out, especially with the top up, is going to get old fast. I used them year round for a few years but a pinched nerve meant going back to the barka loungers for a break. I actually find them more comfortable because they keep you from slouching.

For a racing seat definitely worth the money since you dont need additional hardware they bolt right into the existing holes. You just have to be careful with the wires.
If you score a good deal on a second hand pair you'll easily get your money back.