Well let me tell you my experience today. Dropped my phone and shattered the screen. No big deal, because they fix these everyday.
I go up to the closest iPhone repair place and get it fixed. 30 minutes. Well, I get it back and it just doesn't seem right. The screen has this very strange blue tint, it's missing the dot for light collection to adjust brightness, something looks off with the speaker, and the front camera hole doesn't line up correctly. I compare it to a model at the AT&T store, and it's way off. I have polarized sunglasses, and it looks like a hologram through them.
So I go to another place. 30 minutes. Can't even tell I broke it this morning. Right back to normal. Perfect job.
TL;DR: pick a reputable place when getting your screen replaced.
I had my battery replaced in my 4s, all the issues went away. The back of it is cracked but its in a cheap case that gets the job done.
Glad yours is working!
My issue is that my headphone jack barely works, camera is dirty and speakerphone no longer works. Dont know if i want to pay to fix it or just replace it.