Good call. The problem is that he played in the 40s & 50s and most of the fans nowadays haven't even heard about Gre-No-Li As for the OPs question, Zlatan is clearly better.
Mostly from Celtic fans, I presume? And you can't blame them, they saw him every week in his playing days at Celtic and of course they are a little biased. For us, outside the Celtic Universe, the question is a no-brainer. Zlatan is (or should I better write "was") the better one. I mean, you are doing the same in your thread: I think it's time we had a serious discussion... where you are rating Coutinho-Firmino-Mane higher as Neymar-Suarez-Messi. Seeing that you support Liverpool this is also a bit biased, right? I would probably doing the same when I had to judge a HSV Striker against actual Bayern Striker Robert Lewandowski. Problem: We don't have strikers atm