It's been decoded? Sounds very fake. I also would never trust a website that sells watches with a warranty allowing only their exclusive repair service for their watches. A real Tag can be repaired by any authorized Tag retailer. In fact, I was just online at Breitling and their front page warns that 99% of all Breitlings sold online are fakes.
If you want to save $$ on a real Tag, I have a suggestion - you can purchase Tag Heuers and other fine watches in St. Thomas/St. John USVI for less than what you'd pay in the states. They are listed as certified retailers
by the manufacturer and are legitimate places to buy authentic timepieces. While traveling I purchased an Omega and a Breitling from an authorized dealer there and I *think* they can do transactions over the phone (shhhhh!).
The savings is similar to what you were quoted - we saved about 35% on our watches and a quote we got this spring (while in the USVI) couldn't be matched by our local jewelers.
Since I don't want to advertise retailers, you'll have to search online for where to go. To help you out, I know Omega and Breitling dealers
also sell Tags and you can find their certified USVI retailers on their websites. Anyhow, it wouldn't hurt to call and check.
HTH!!