Not sure that it is called "die cut" but you are correct the vinyl media is cut via a plotter that uses a tiny needle to cut the pattern out so there is no background. All the vinyl I use is 3-5 year exterior grade, meaning uv is not a problem and it is ment to take a beating. I have some vinyl stickers like these on my car and they have lasted for about 5 years and the edges are just now getting a bit "choppy" from general wear. The life of these is greatly reduced if the installer doesn't properly clean and adhear the sticker (Instructions are included). So long as you are not GRINDING the mud into the vinyl they should have no problem lasting 3+ years.

Hope that answers your question.

For some background:
The place I work used to be a full service sign shop. We quit that about 4 years ago to started doing architectural cladding (metal panels that go on car dealers like Toyota, Nissan, Mazda etc) I still have all the old sign tools available to me so I just go into our graphics office and run these or any design I want after hours. So these are not some joe blow made crap. Besides they are only $5 so if you destroy one putting it on or rubbing it against a tree I can get you another for $5. <img src="/forums/images/graemlins/smile.gif" alt="" />