I am pretty new at this candle making ( about 1 1/2 years) but I use ezsoy and 6006 (both from bcn) and there is no wax residue or soot on the sides. Of course I have found wicking the right size makes a big difference. As far as sooting,, I no longer "blow" out my candles but dip the wicks and found my candles don't produce any soot.