For me, the warranty means very little. if installed correctly, what will fail?

I would use it on the steps. JUST MY OPINION.

I am actually thinking the same thing. It's funny how the instructions say don't do it but they also manufacture the stair nose for the particular LVP I want. But since its a DIY I did not know if I should care that much about the warranty. Thanks for your opinion. :)

INstall on the stairs if it is glue down LVP it will be fine I have had LVP on my satirs to the walk out basement for 18 yrs and 3 huge dogs still looks great .

The stair nosing is manufactured to meet up/finisjh with the LVP such as a stained to match or blend wood stair will meet a hallway landing on a second floor that has that LVP installed on that floor. It is not to suggest the LVP is fine on the stair treads, and hence the "warranty void"

Stairs are code to the merest fraction of an inch, ( tread, rise etc. ) I would not DIY a stair., ANY stair .........just saying.

For acoustics alone I would carpet from the stairs on up through the bedrooms. Painting is not a look you want and certainly not when they stand alone. They ought to 'match' where they are going or where they came from.

I would carpet the stairs if they are a straight run with no landings in the middle. Slipping or falling on stairs is painful and dangerous. It will also help with muffling noise anytime someone goes on the stairs.

Carpet, including hallway for safety, simplicity and quiet.

Hope this helps. Our basement flooded and we opted for LVP (that worked with middle floor’s wood stain). The installer then purchased non stained wood treads/risers, tested stains and its really hard to see the difference. Were so happy with the result, we removed the carpeting on the upper level stairs/bedrooms and did the same and added a runner in the hall.

I think painted stairs suit specific styles and I’d avoid carpeting.