I trust my life regularly to off the shelf webbing while climbing. Lets err on the side of caution and say it does suffer from UV exposure, and you're going to want to replace it once a year, or even twice? I pay about 30c a foot for 18kn rated webbing, and it takes all of, what, 5 minutes to rig them if you have the tie off points/cleats installed? Sounds like a win to me.
disclaimer: I am not a rigger, nor do I have any professional expertise with boats or life saving devices.