Warning : I’m extremely biased in favor of that lens. I’ve had countless units of it. I buy it, love it, sell it for something supposedly newer and better, or just because I needed cash, or changed mount. Then bought it again, and so cycle went on, and on.
I owned it in Nikon mount (several copies), Canon (several copies), Pentax (1 copy) and Sony (1 copy). All of them were the original “without AG motor” versions. An urban myth suggested that, optically, it was slighty more desirable than the newer, “with built-in AF motor” model, designed for low to mid-end Nikon DSLRs (3000 and 5000 series). Of course my Canon units had a motor built-in, as Canon bodies don’t.
The usual test, a random abandonned toy (my house has them aplenty…) at the lens’s widest aperture…
All the 28-75 units that I had were, at least, very good. Some were excellent. Some were superlative. The current one is the “with AF motor” version, and what can I say, it is absolutely great. I used a spanking new Tamron 24-70 F:2.8 VC USD last week, and while and excellent lens it didn’t strike me as better than the older 28-75 in ANY area, whatsoever, and it’s about 2.5 times the price. I’ll stick to the old lens, thank you very much 😉
Our two rescue girls, Google and Juana, perfectly captured by the Tamron and D750.
So while newer is usually better in digital technologies, some oldies are indeed, goldies. Now off to the 2015 Paris Horse Show to put this baby to work. Stay tuned !