What's your favorite brand/style? I can't decide but I want something mlok that's more heat resistant than anything. And I also need a couple 2 inch picatinny rail covers. So if you have the time I've got the ears
BCM and Magpul are kinda the go-to, also check out Railscales. As far as heat transfer, most are just thin plastic or polymer and don't really provide much insulation from barrel heat. Rail wodth would help more. IMO