Wellll.. pretty much any colour neg film I have ever used can give unrealistic colours if it is overexposed. Overt the years I bracketed quite a lot in 35mm to learn the ropes, and when I compared the brackets, it was quite clear that they differed substantially.
If you rate reala at 50 or something, then, sure you will get more saturation in the primaries and less nuance overall. But that is also true of every colour neg film I've ever used. At the same time, metering technique is just as important as how the film is rated, if not even more so. It seems that the best way to compare these films is to colour meter off a neutral object.
One other issue, the importance of which I can't assess at all, is that some claim fuji films do better in fuji chems; kodak films do better in kodak. This sounds reasonable but I don't know firsthand how much of an issue it is. Some of you know, and I'd appreciate comment.
The bottom line I suppose is that you can get spectacular results from any of the modern colour neg films. It is hardly surprising that all those years of research produced these extraordinary films. That said, I still love my astia