Firstly this is comparing the actual screens not the size. As for the discolouration issues, I don't think there are many out there and what the Antenna issue has to do with the screen, who knows because I certainly don't!
IMO unless you are watching films the Iphone 4 display is superior. Where the SAmoled screen has richer colours and deeper blacks, the colours aren't necessarily true and have an overbearing quality on the screen (btw I am using the Wave rather than Galaxy, same screen though). My biggest issue with the SAmoled screens are they are still PenTile Submatrix screens, the resolution is interloped and far less than the claimed. Read this thread about it, also on XDA forums. For reading any type of text including E-mails, books, web pages etc etc there is a noticeable difference. Don't just be fooled by the colours, there is alot more to a screen!