I think Retina is nice, but some of the comments here are overblown. The only way you will know for sure is looking at both of them (iPad 2 and 3/4) side by side. When I did, I could tell the difference, but it wasn't like OMG, the iPad 2 it TERRIBLE. The iPad 2 was fine. The iPad 3 looked a little bit better. I think that part of the confusion is that despite being twice the resolution, everything looks the same size on both versions. One looks sharper, but the other one doesn't look THAT bad. It actually looks great.
I recall the word "magical" being used to describe it when it was first launched. So since nothing about it has changed since it launched, I can't understand how it went from amazing, magical and awesome to CRAP just because Retina came out. Its too big of a swing. It may be for you as well if you see them side by side and say "OMG, I could never go back to that crappy iPad 2 screen". However, I doubt most people would react that way. Me, I think the iPad 2 looks pretty good.