Hi, I've not seen or heard of Power Bass speakers before. They look remarkably similar to the custom fit Focals, but the spec is different, lower sensitivity and the materials are different.
In the USA Power Bass are around $130 and Focals $300+, a significant price difference.
The UK the price difference is only around £25, so for that I'll be playing it safe and going with the known quality of Focals.
I've had Focal K2 and PC speakers in another car for 6 years, no issues.
OE Series 6-1/2" component speaker system for select Toyota, Lexus, and Scion vehicles
www.crutchfield.com