I just rode to/from the BMWMOA meet in Bloomsburg PA last weekend - 1400kms - in a 'stich onesie. Rode with the stich, boots, full face helmet behind an aeroflow on my GS and... I didn't mind it at all. It was 38c plus humidity when I was riding. It sucked when I stopped, but moving I was perfectly fine. I actually found it more comfortable than my old Olympia AST/Ranger combo. Keep the zips open and it's comfortable. Did I sweat? Yes. But constant hydration from a water bladder in the tank bag solved the lost fluids. You take in a lot of water/gatorade (I alternated). I refill the 2L bladder at every gas stop. Shorts and a wicking tshirt are key as well to keep your temp in check.