I would never take notice of that site regards Sony as they always seem to down rate Sony lenses in my opinion.
For Canon, I would be happier looking there.
I think a large part of the internet hate for the Sony APSC kit lenses came from that sites early reviews and the Sony kit lenses were about the same to me as those from the other players and a bit better than some.
I have had kit lenses from Nikon (two), Canon, Pentax, Olympus and Sony and while none are any more than kit lenses, I rate the FF 28-70 the best of them and then the Canon 18-55 IS ii (that can be used FF on Sony from around 24mm and up) and then an APSC Sony kit lens I had though again, all were fine.
I think the consensus (Photozone aside) seems to be that the 28-70 is not garbage and IS worth the money when found cheap especially.
Where the (often circular) debate comes is mostly how well the 28-70 compares with the 24-70 and given the price difference it should not even be mentioned alongside the Sony Zeiss.
When released they were two of few lenses for the system and it was only natural to look at them (other than on price).
Respectfully, my copy of the 28-70 was really bad. I had an old, tiny $50 Sigma 28-70 f/2.8-4 that was MUCH better throughout the range. It does sound like there are good copies out there that rival the 24-70 f/4, though. I've actually started trying to find one that's good stopped down and posted on the buy sell board....but maybe it's just a matter of people comparing good copies of the 28-70 with bad copies of the 24-70? So tricky to deal with sony's QC....I think at this point I may wait for next year's tax refund and pick up the more expensive lens used at that point.
I don't think the 28-70mm is garbage but holistically the 24-70mm is a better lens if you care about higher contrast, punchier colors, 4mm wider on the wide end, better build quality and a constant f4 aperture. The sharpness is close but I always felt the image rendition from the 24-70mm to be better overall compared to the 28-70mm. The ~$500 used premium is generally appropriate when you take into account what you're getting.
Personally, I'd rather pay $500 for the 24-70mm f4 or the 24-240mm than the 28-70mm. The increase in versatility and/or better image quality is worth the cost. I would feel the 28-70mm would never get used by me as i would rather use better lenses that I have than ever use that.
I have had both the 28-70 and the 24-70/4 and the 24-70 is overall better except at 70 where neither is particularly good. If you want something really special, that's challenges primes, it's not the lens to deliver that. I have found myself moving more to zooms, and have now settled on the 16-35/4 and the CY 35-70/3.4, which can challenge primes. I keep the 28-70 for when In want AF in situations such as social or informal people pictures, and it does a good job there. As someone mentioned, keep important stuff out of the corners and it's a very useful lens. That it's small and light doesn't hurt.
