The key to good “vinyl woodgrain” lies in its ability to resist UV radiation from sunlight. The only product that I’ve found that really holds up well to sunlight is the original 3M DINOC. It’s interesting that the individual you reference says that the “Spartan” has held up well for 3 years. It would be more interesting if this person could provide some detail of the conditions, how much time does the vehicle spend exposed to sunlight and what part of the country is he from? If the car is garaged most of the time and he’s from, say, northern Montana, then his results will be far different from someone in Texas whose car is outside 24/365.
DINOC is still being sold on Ebay, but I don’t know if it is the same product as was originally supplied to GM for our wagons. I recently heard some things that make me think that this might not be the case.
I purchased some 3M vinyl woodgrain from “Stripeman” about 3 years ago (at a high price) and it has performed very poorly. For just over $100 I obtained enough to cover the light wood trim moldings on my ’95 “Roady”. After two years in PA, it started to break down, and now it's disintegrating.
My current solution is to replace it with vinyl from “dcFix”. I’ve used it before; it’s inexpensive and great looking stuff, and easy to apply---but from prior experience—it will not hold up well to sunlight. So I’m going to try spraying it will clear UV protectant, which is available in “rattle cans” from both Krylon and Rustoleum.
We’ll see, I guess!