I may just be unlucky, but I just recently acquired my second copy of the 28-70/4 after I gave away the first copy because it had some haze and performed poorly, and now my second copy, which is clean, performs no better than the first and IMO is worse than the FA 28-80 I own.
I don't think the 28-80 is a great lens by any stretch, but I think it's better than it often gets credit for.
I'm not sure about the 28-70/4, I would love to get a copy that's as good as the reviews suggest.
I've never used the FA* so I can't comment.
As previous posters have said, the PF Review rating are quite subjective and I think that the ratings are based a lot on whether the reviewer feels they got their moneys worth so to say
I gave the 28-80 an 8 because, for $30, what can you really complain about.