Alternative To Bondo?

Im an autobody tech, bondo isnt bad stuff. Ive use napa's brand and i have to say its the worst brand that ive used, and its more expensive than bondo. in the shops that Ive worked in they all used 3m's platinum body filler. It spreads really nice and sands easily without clogging up the sandpaper. Dont mix it too rich or too thin, we mix the hardener 2% by weight.