Originally posted by oddie1990 Just a word of caution here. I was into Henry's on wednesday to talk about the new Sigma 70-200mm, f2.8 lens that I had bought. It works fine. Anyway, the rep told me to tell my friends etc. NOT TO BUY the Tamron 70-200mm lens as they had customers come back with defective lenses. This happened a couple of times. Then they decided to try some new stock on their own cameras i.e. Henry's in stock cameras. Low and behold, the Tamron lenses worked for a couple of days and then started to act up and finally would not work. So it would seem that Tamron has a few bugs to iron out yet, despite having superior optical glass in them. I almost bought one of them, but the ten year Canadian Warranty on the Sigma lens was to hard to resist. If I remember Tamron has a 6 year warranty. For what it is worth - just be cautious when deciding what to buy.
Oddie, you can be sure that if there's a QC issue or defect in any lens that can be mounted on a Pentax, it's certainly been discussed many, many times on this forum. :P
Tammy 70-200 issues have been well documented here, as have Sigma 70-200 EX II problems.
As long as Tamron keeps the same optical formula, I'm sure this is gonna be a helluva lens.