Has anyone used a DETMAR inline fan or bilge/brake 12volt DC fan?

I notice they have 4" blowers that put off 240CFM, they're not badly priced around $30ea shipped..

http://www.detmarcorp.com/blowers.htm#4inchblower

I was wondering if anyone had used these to vent anything and how loud they are?

They look awesome because I'm thinking they can be powered by a computer power supply or a 12v 5amp DC adapter..
But a computer power supply I already have and it's laying around so.. that seems like a good option hehe..

I'm also thinking maybe a computer fan controller will work on this fan? As long as it's rated to hold that amperage..

But I need to know how loud they are?
Does anyone happen to know?
I would really appreciate some info on these if anyone has some..on how loud they are...stuff like:
do they put off a high pitched whine?
are they nearly as noisy as an inline fan on a fan controller?

These fans look good and they say 240CFM..
I am not filtering the box I want to use them on so..

Any input appreciated on that stuff..thanks,
-C

has anyone used these at all? or anything similar? Like from Attwood or anything?
I'd really appreciate the noise info...

Dead thread, but they're loud. I use one for intake, works well, but loud.