On the Tampo, I assume you used a paint gun? It lists quick dry, and high solvent resistance. How is it for tool cleanup. Alot of materials designed to be used in industrial applications can be a pain for the DIYer. And what kind of coverage did you get? I guess we'd probably need the big can for a full set of panels.
My brother used it before I did. He re-coloured the interior on an old Brit. car he was doing. He used it in a spray gun and also tried it brush on and found there was no reason to spray it as the results were indistinguishable.
So when I did mine I applied it with a soft brush and it was fine. The main thing is to make sure you have the surface VERY clean and dry (especially on ABS door panels as they retain moisture - best to leave them by a heater in the house for a day or so). Once it is clean and dry I think a wipe over with thinners is a good idea to be sure the surface is ready.
I did all my door panels and seats out in the yard with some warm sunshine and I worked in sections brushing the ink on and then patting it with a rolled up rag while it was still tacky (it does dry quickly). That took away the really high gloss that would have been to much. The result is really good. It looks just like a regular '70s vinyl finish.
I used black over gray and it covered easily. My brother used black over red and that covered easily too. There is a lot of pigment in the ink and I would think you can cover most colours easily one way or the other.
As for cleaning up - they list a special thinner but it is expensive. I used cellulose thinners and it worked OK for thinning and for clean up, but I didn't have to clean up the tools anyway as it was only a brush and some rags.
Also the hardener they sell is an isocyanate hardener like you would use for a laquer coat, so you don't need to buy their special hardener if you have some of that anyway.
Although it dries quickly to the touch, it doesn't cure properly for a day or so. The ABS panels can be scratched quite easily if you try it a few hours later, but after a couple of days it doesn't scratch at all unless you really beat on it.
I got 1 litre and it did my interior panels and seats with only about a third of the tin. But I think 1 litre is the minimum order.