I just started using the oracal 651 3 years ago, it on my vehicle, it shows no signs of shrinkage or cracking.....normally you wan to use a high performance vinyl on a vehicle, but i knew i was going to change it every few years. Hope this helps.
651 Outdoor Durability
(based on vertical surface exposure) 6 years, 4 years metallic, 3 years brilliant blue
BUT PLEASE don't take that as i am recommending you use it
in my opinion material is (or should be) such a small cost in the work we are doing use the right material for the job premium CAST. why take unnecessary risks. do it right or do it twice...if the client gives you that second chance.
The reason I asked was that I have a roll of 651 that I will probably never use the rest of (gray). It's going on an oil field truck that they will not keep longer than 5 years. At that point it will be pealed off anyway when they sell it or trade it in.
I've got two fleets with vans going back almost 8 years all done in Oracal 651 & 751. The 651 is holding up better than the 751. The only noticable aging on the 651 is a loss to the gloss and the red is fading on the oldest jobs.
I think for what you are asking for, use-wise, it should be OK.
But I am like the others, only cast on vehicles and "good" signs.
I do use 651 on windows, coro, and banners.
Have had both red and yellow fade after about 18 months.