I put the Herculiner on my basement stairs about 7 years ago, and it is still holding up alright.
I did the tread section of the 2x12, first patching with flash floor leveler ( like you would use for under lineolium floors ) to get the thread smooth, prior to putting on the Herculiner.
I will say with the foam roller, you can really lay it on thick, so I don't know if I would believe that you can spray it thicker then roll it on statement.
I have one heck of a build up on the tread, where it stands up noticably higher then the white paint around it ( put the paint on with a 1" nap roller ).
The treads are not as grainy as they used to be day one, but they still work fine. I spilled coffee on 2 of the steps on night, and I had to go upstairs to get a towel, stepped right in some coffee I did not see, and guess what...no slip
Thing is, if it is a DIY or a spray in version, once they wear down, to re do them you have to use an angle grinder to take it out, before re coating. That is what the Line-X dealer at the Chicago auto show told a friend of mine ( his is really old, brand unknown, and needs to be redone ).
When is comes down to it, are you looking for this to cover damage already done ?
If not, get a rubber bed mat. You can abuse the snot out of them, and they stand up for it. 100% no slip load securing, and if it gets damaged, it is like another 80.00 to pull it out and replace it, if you can get it that bad. Given the rubber bed mat does not cover the side walls, but WTF it is a truck, it is going to get dinged up a bit from actual use
Either way you go, good luck