The longest I have test burned my candles is 4 hours and then I burn them again the next day for 4 hours. I do trim the wick though. How long would you consider a power burn to be? 6+ hours? What I am looking for when testing is full melt pool, no or little mushrooming, temperature of glass, and flame height. Obviously scent is important as well but I'm trying to evaluate the other factures first. However my scent throw has been awesome too. To clarify my glass tumbler is 3.25" in diameter. 7.5 oz, 8.5 to rim. The recommended wick was an eco 8, so I went up two sized due to all my candles having dye and an 8% FO. As for the mica, I'm a little perplexed. Many candle suppliers sell the cosmetic grade mica I use. I think it adds a lot of elegance to the embeds I make, and since it is not added directly to the poured wax, I didnt think it would clog the wicks that much. I am new to candle making though so all of this feedback is so much appreciated.