Looking for past or present users reviews or findings of any brand of specifically plastic, polymer, or plastic looking but supposed phenolic carb spacers, preferably interested in the 1/2” 4-hole versions but input from users of open as well as thicker versions are useful as well. What intake was/is used, heat crossover open or blocked, Air Gap style DP and single planes etc. Seeing and reading some used with no issues, others had melting and warping. Problem is in most cases the users haven’t divulged specific details of the intake used and/or whether a heat crossover is operational. A few pics found from searches: Just running an aluminum or using the wood/fIber is the obvious but....So now that that is out of the way, plastic users what say you?