I don't get the fuss over the Cayman GTS.
Based on the Boxster S and Cayman S, the new GTS models benefit from an enhanced 3.4-liter flat six that produces 330 horsepower and 273 pound-feet of torque in the roadster or 340 hp and 280 lb-ft in the coupe – representing an increase of 15 hp and 7 lb-ft in either model. Both also come with the Sport Chrono package as standard, along with adjustable suspension and 20-inch alloys, blacked out to match the dynamic headlight surrounds and other muted trim.
I'd rather get the M235i.
The GTS is an S with all the performance accessories. The power difference is just the exhaust. It'll actually depreciate better than an S with options and be cheaper, so it is a bargain as long as you don't mind seat embroidery and are fine with black interior.
The GTS is a LOT more expensive and the M235i is a 235i with an M on it. Don't let the M distract you; it needs a better diff and stiffer bushings.