I had the smc kit on my 02 wrx and I was running 100% methanol. The only concern I had was if I was stuck in traffic and it was hot outside (100F plus) I could smell the methanol vapors if I rolled down the driver window. Other than that I had no problems I live in an area that gets up to 118F in the summer and it worked fine. Plastic is an excellent insulator and if the meth is evaporating it's going to take a lot of heat to get it to boil (the conversion of specific heat to latent heat will keep it "cool"). I just worried about filling my engine bay with methanol fumes while sitting still for long period in which case it would only take an ignition source to turn my car into a firecracker.