I will start by admitting that I rarely use pot holders, preferring towels, a holdover from restaurant days. But I have lots of friends and family who cook in my kitchen and expect pot holders. My latest purchase - SLT - do not block heat well. Although they are double thickness, it is impossible to hold anything very hot for any length of time.
Some old pot holders were much more efficient, alas they have holes and are destined for the rag bag. Who has great experience buying pot holders that really work? I would appreciate hearing the 'who what, where, when & how' of your successes. Color is not important to me, efficiency is foremost.
NB: I should add that I do not include those bulky oven mitts in the 'pot holder' category. I am looking for square-ish pot holders capable of blocking heat.