So, basically same price.
The Tamron is an Adaptall 2, is MUCH bigger and heavier but is faster and makes some stunning photos. But, you know, its about 4.5 pounds.
The A* is smaller, lighter, more packable. It also makes some great photos. It is also, generally speaking, a tad bit easier on the wallet than the Tamron. From the samples that I have seen, the A* does not isolate the subject quite as much as the Tamron can.
How will it be used? On a film body only. Will not be used on a digital body so all of the CA that everyone talks about is not too much of a problem/ concern to me. I will be using it for automotive photography so it, whichever, will be mounted on a tripod or monopod at all times. I know that the A* could be handheld but the Tamron not so much.
So, what say you? Sure an F* or FA* might be a better option but that is WAY more than I wish to spend. I am leaning towards the Tamron based on the photos that I have found where it is pretty damned sharp, even wide open. I have not found too much in the way of A* showing a ton of isolation. I am looking to be able to take whole car shots where I can make the car 'pop' a little more.
Here is an example. This was with my Bronica ETR with a 200/4.5 (around 130mm on 135 format) at 4.5 on Ektar. I am looking for a little less DoF
Obviously, I know that this is in 120 and not 135 but I use both formats.