I've been wearing one here in S. AZ for a couple of weeks, and I don't really see it as being any cooler or warmer than my previous concealment garment, a untucked cotton button-down shirt. The thing to keep in mind with the R-R vests, shorts, pants, etc. is that they start with heavier-than usual fabric, and double-stitch it in double (and, in places, quadruple) layers...so it's gonna be pretty heavy as it is. If you want the carrying capacity, the vest has that in spades, but you gotta put up with a little more weight than an untucked rugby shirt. If you don't want to deal with the weight, either wear that shirt(which can't carry jack) or don't carry so much stuff in the vest. One thing you can do to drop some ballast from the R-R vest is to pull out the big velcro panels inside the concealment pockets - that should drop the (unloaded) weight of the vest from 2.5# to just under 2#.