i was interested in the sigma 18-35 but they are not in stock anywhere here in the states so i bought one from digitalrev. it arrived and i loved the lens but it had really bad af issues. their website states that they have a "14 day no questions asked return policy". i submitted a return request in that time but did not hear back from them for a few days at which time they "regretted to inform me the return period had expired". some emails back and forth and they agreed to accept it back with a lot of "ifs". i have to pay return shipping and if they determine its a manufacture defect they will reimburse etc. i shouldn't. have to do this but i got a sigma dock and spent all day getting to work in a usable way so i am still happy to have it but i would warn anyone considering buying from them to keep this in mind.
There's several angles here to consider. 1) Sigma dispatching a lens with heavy AF calibration issues. You are not alone in this and it's happend to me a lot from Sigma and is one of the reasons I avoid Sigma lenses. Sure a little calibration is to be expected, but some Sigma lenses are excessive.
2) Sigma sell a device for the customer to correct something which should have been done in the factory. You are out of pocket for the cost of the device and the time it took to calibrate the lens. Again, this should have been done in the factory.
3) Digital Rev are selling you a promise of "no Quesions asked" returns policy when in reality they are asking a lot of questions and putting a lot of caveats in the agreement. I have used DigitalRev a number of times and I've never had any issues with the pro Canon gear I've bought from them...but I certainly wouldn't want to test their warrenty or returns policy. The postage back to Japan would nummify any profit margin they have and thats probably why they are trying to wriggle out of their promise. You've done the right thing by putting this on a forum, vendors should be transparent with their customer service. you might want to drop them an email pointing them to this thread....I would
One of the reasons I buy Canon L grade lenses is that their AF calibration is covered in the 1 year warrenty here in the UK. If a lens is out of whack (only one ever) then I can either send it back to a UK based seller (I don't buy lenses from abroad), claim the situation back from my credit card insurance or send it into Canon for a calibration. The red ring isn't just about image quality....it's an expectation of service.