It looks like the lifespan of the very sharp and renowned Tamron 17-50mm F2.8 VC and non VC is coming to an end. This lens (which I owned) is finally being discontinued, being the staple diet of many a photographer on a budget for what seems like ten years or so.
With many lens producers revamping their lens range, maybe this lens is being targeted to be replaced by Tamron with a lens that has the build and feature set that was lacking slightly in the earlier model, both it and the Sigma required the camera body to be switched to manual.
Clearance sales are popping up and the lens can be found new on line (Priceminister) for as little as €160 for the non VC and €172 for the VC version, the non VC being the sharper of the two.
A quality F2.8 constant lens for the price of a 18-55mm kit lens!
....Now do I get one?