I had a car full of Polk/Momo stuff, it was in thier booth at Nopi 2 yrs ago, it sounded great, and was quite loud. I also had a buddys car in thier booth this year w/ favorable results. The db series is true mid-line stuff Better than AudioBahn and those companies, but no MBQ, Diamond, Boston.
Its the best for the $$ I know of. I still prefer Diamond Audio, but its hard to eat steak on a hamburger helper budget.