One thing I've learned is that most screen protectors cause more resistance when using a stylus. However, I was only using a stylus to minimize prints on the screen, and with the screen protector, I don't get the prints showing as bad, so the trade of there is fine with me.
I finally upgraded to a Lumia 520 a couple of months ago. Before that, I was still using my HTC Wizard 8125 that I bought in 2006. I finally dropped it hard enough to break the battery cover.
Since I tend to keep a phone for a very long time, I opt for the screen protectors, because 8+ years can see a lot of scratches.