I bought these for my 87 GMC S15. My truck is a base model so it didn't come with speakers behind the seat and not was it pre-wired for them. There was also no factory mounting hole. Luckily, Crutchfield included mounting brackets free of charge. In a higher trim level, my truck would have come with 4x10s in the rear. I am somewhat of an audiophile and I believe round speakers produce a more accurate sound but I didn't want to hack anything to make room for round speakers, which is why I compromised with these elipticals. Out of the box, I felt they were made well. No sloppy glue joints or anything. I went a little overboard in the installation, lined the speaker cavity with GTMAT insulator to cut down on body resonance and used egg crate foam to absorb the sound waves from the rear of the speaker. I also installed the KS46s in the front. I feel these speakers were a perfect match for my JVC head unit at 20w rms per channel. They were a definate upgrade and being a coax speaker, having tweeters was a huge improvement over just having 2 stock speakers up front. To my ears, they still sound like eliptical speakers, but elipticals have come a long way. Overall, I am pretty happy with this setup. The sound is much clearer than before, and they produce a good punch for their size. Don't expect to feel the bass, its a small, low watt speaker. However, if set up and powered right, they sound good. I think my set up even sounds great out side of the truck.
Pros: Made well, Cructhfield included mounting hardware and oem wire connectors, big improvement in sound quality from stock.
Cons: They are eliptical speakers, a little more expensive that the competitors.