Be glad that FR is using the vinyl. I consider it to be a very nice perk. Two years ago, when I was doing research before buying a new unit, the use of vinyl (TPO) was pretty much exclusive to a few high-end units. One major benefit is ease of care compared to rubber (EPDM.) The warranty is the same as rubber, 12 years, I think.
See the last two paragraphs on this page. Also search for TPO.