I have used it on our boat and it is great. I have no carpet in mine now. We have kids and love to fish so at the end of the day, pull the plug and wash out. No slipping at all. I did however help a buddy with his and he used this rubberized non skid covering from overtons (it is a lot cheaper and works great):
I used a total gallon on my 19ft open bow. Just depends on what all you plan to cover with it. Wether you are doing the gunners, engine compartment, and how thick you applying it. Their website should give you an estimate on how much square footage it covers and compare that to the square footage you plan to cover.
There's a product called Marideck http://marideck.net/products.htm that is designed and marketed specifically as a carpet replacement. Not necessarily recommending it over Durabak or anything else, but you might want to check it out before you commit. I have no experience with it.
