Is the s3 a bad generation of galaxies?

I have the s3 and it's my first smartphone so I don't really have anything else (such as an iphone) to compare it to.a friend of mine-who has owned the s2, currently owns the s4, and whose parents use s3's- told me that the s3 and original galaxy aren't as good as the 2 or the 4…

the s3 is obviously a step up from the phone I had a year ago and I'm grateful that I have it, but I'm not too pleased with it and was thinking about making my next phone an iPhone. After hearing my friend's input though, I'm not sure anymore.

what do you guys think?

I have the s3 and I have not had any problems, but this is my first smart phone so I have nothing to compare with. I previously had a pantech touch screen.