Products like Noico 80 and Dynamat Xtreme, while they are butyl rubber with a foil layer, they are still not touted as waterproof, heatproof, or oil resistant. It is recommended to install another layer or liner on top that adds the particular type protection you need. In the Dynamat World, they are several choices (DynaPad, Dynaliner, DynaDeck etc.) to meet these needs. There are many other cheeper competing products as well that can do this job.
That said, for typical automotive usage, I wouldn't worry about water issues with the Noice. I have the full stock carpet and deep well mats on top of that just in case of an accident. But, for a Jeep that has the tub washed out with a garden hose, the risk would somehow be getting water into a sound mat seam and having it seep down onto the tub surface where it could get trapped and not evaporate quickly. It would be wise to just install a permanent (or semi permanent) waterproof layer on top to protect your sound deadening layer, if you wanted to try something like this.
For me, if I was mainly off-roading and not using as a DD, then the Bedrug liner or DynaPad looks attractive. However, with just the liner, you wouldn't achieve the same level and quality of sound deadening as with the professional quality butyl sound deadening mats.
I'm considering installing some liner or velcro carpet pieces in two spots because of this (for a LHD Jeep, this is to the left of the drivers feet and to the right of passengers feet where the carpet does not go all the way up the side of the Jeep ). That said, it really doesn't bug me too much, it would just be a nice finishing touch.