I have to admit that I haven't carried a throwable device ever. But it does make sense to carry one.
I have this same NRS throwable bag from my rafting gear and may start including it in the onboard kit. While it will not qualify as the Type IV device, it is actually massively more useful in our situation. Depending on which throw bag you purchase you can get some extremely high strength line in the package which is more useful for all kinds of things besides just a throw line. Like for getting a tow when the shipment of air in the truck doesn't show up on time.
I have had onboard inspections several times aboard This End Up and the local officer past up on the Type IV throwable and were really only interested that we were wearing appropriate life jackets. I have had them pester me on the whitewater raft for the Type IV thing and I have just subtracted the 3" from the actual length of my raft and told them the rafts are 15' 11".(they are actually 16' 2"). A big cushion might be justified on a light air day, but for our purposes they are really just in the way. The throw line on the other hand is massively useful, so if they ever ask I guess I will have to say that my 5.2 is only 15' 11" long (for sure they are not going to have a measuring tape).

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dg
NACRA 5.2 #400
This End Up
Original owner since 1975
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