I bought these speakers for one reason: to make bass. The 5 1/4's were installed as door speakers, powered by a 100watt amp, with no subwoofer. The vehicle has since been outfitted with a Bazooka sub, which produces far more bass, but these definitely gave a lot of bang for the buck.
Only complaint is that one of the speakers developed a very subtle distortion early on, before it was replaced. Don't know if this was a defect or just very mild damage. I have, unfortunately, blown the speakers more than once sending too much bass at too high of a volume.
But otherwise, no complaints. They've tolerated a lot of abuse, and stood up as well as I'd expect.
(Note that I'm not rating quality in comparison to any "higher quality" speaker... these were replacing a rather poorly configured pair of cheap 4" speakers that made no bass. But I've yet to hear a pair of 5 1/4's make the lower frequency pressure that these do, while still sounding good in the mid/upper ranges.)