IMHO I prefer Sonus....it's more expensive, but it is a high quality product. The PB 3 and 2.5 just don't have the cutting power along with the quality polishing that SFX1/SFX2 have. This again is my opinon. I know people really like PB products. So I thought I would give them a try. Maybe I'll have more luck with them on softer paints. But the sonus SFX line is very trustworthy and can make a beginner look like a pro! You just have to shovel out a few more bucks than you would on the PB line.!