well I've never heard of this type of fan, but I don't own a boat either.

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there cheap and the cfm's are equal to a couple of the 4" inline fans ive been looking at.

The only problems I can see are it not being meant to be run 24/7 and the noise, any use one of these in their room?

only problem i can see with these is they are 12v only and not particularly quiet either

The volume flow rates or CFMs as you call it may be impressive, but volume flow rate on a test bench is meaningless, unless that's what your gooing to sit and and admire it.

You really have to know what power it develops, which translates to it's capacity to overcome resistance ( i.e. ducting bends carbon filters ) Just looking at the design I would say that just putting your hand near the discharge would cut the volume flow rate dramatically, just as with a hairdryer..sounds like one too. It sounds like it's going at a very high RPM, so flow would be needed to keep it cool. I imagine that if you put it in typical growers situation it would burn out very quickly.

The're very cheap, so it might be worth actually testing it.