I replaced my Ford Focus 2005 hatchback's stock speakers with these, on the front panels only, because the left speaker was always low volume, and a technician told me that it might be defective.
I needed to grab a set of Metra 72-5600 Speaker Adapters separately to be able to connect the speakers to the cable in my car, but other than that the mounting holes were surprisingly close to stock.
I recommend using the included bracket with these speakers, as mounting speakers directly to metal can reduce sound quality. It's important to be sure that the speakers are snapped tightly (and completely) into the bracket which may require some adjusting and pushing.
After I installed the 2 speakers I bought into my 2 front door panels, I tested them out and was surprised at the sound quality increase. The mids were slightly better and clearer, the bass was noticeably better and present, and the treble/highs were much more vivid and clear. There was more separation between all the sounds too, so it was easier to make out individual instruments/voices/other sounds.
Since these speakers were 50w RMS speakers (rather than my stock speakers' 25w), they could handle more power and did indeed sound better when given more power. I have an aftermarket Kenwood KDC-BT362U with a built-in amplifier which can provide more power than a stock header unit (the radio, basically) so I feel that I was able to drive these Scosche speakers better than I could've with my old, stock cd player head unit. ( I replaced it because the CD player stopped working, but I also wanted bluetooth and aux cable capabilities)
So as a warning: if you have a stock, low-powered head unit, you may not be able to drive these speakers to their potential and they may not even sound better than your stock speakers. If you have a good aftermarket head unit / amp however, you'll probably be able to give them enough power to make them sound the way they're supposed to, and they will probably sound better than your stock speakers.
At any rate, at such a cheap price, they are a great replacement for most stock speakers, especially if your speakers have died and you need to replace them anyways.