Sorry, but the only personal experience I have is with the old Schluter inflatable yellow floats- which Hobbico copied directly and still offer,
AFAIK.
Those floats provided enough buoyancy, but were too short. That's how I found out about the need to keep the tail out of the water...
This was on a Concept 30.
I should have mentioned that it seems to me the open-cell foam stuff would need to have a lot more comparative surface area than a solid or inflatable float. Looks like that is the case. But I have seen the smaller noodles on machines at fly-ins, and the owners said they floated fine. So, I dunno...
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