Hi austinspace:
I have used a couple of these, but I ended up using a Carter Bags one, called a Carter Bag Personal Float. Lemme tell you about the ones you asked about first.
The DAN signal tube is pretty neat, I have one from the same manufacturer but in yellow and it has Amerisea Diver Below printed on it. It is a rugged signal tube but the thing that turned me off was the poor quality-like LPI tube and the bulkiness that it created when rolled. But after looking at other tubes, they all seem to have the cheap plastic like this one. The good thing about it is you could unscrew a collar down and either orally inflate it or use your LP hose. It is a semi closed bottom and it holds air well. It does have a vinyl pouch at the top to hold a Cyalume stick at night and a mesh pocket at the bottom, to store your safety goodies. It will probably come with a Wind Storm whistle, some form of a reflective plastic mirror, and a Cyalume glow stick. All of these are ok quality and are pretty easy to use but the signal mirror takes practice to master. What I didn't like about this setup is that it was so bulky when rolled. I ended up taking the glow stick out, putting the mirror in a plastic bag and replaced the Wind Storm with a Storm (which was bigger). The mirror ended up losing some reflectiveness after a couple of ocean dives (and I thoroughly rinse all of my gear after use). So an upgrade would be a mil-spec signal mirror from maybe ACR or the such.
The OMS bag to me was of cheap quality. It had a semi closed bottom but no provision for LPI. No biggie but I wanted two forms of inflation on my tube. It was country-simple though.
Now I ended up using a
Carter Bag Personal Float, 35 pound lift, 60 inches high, and 5 inches wide. It has a semi closed bottom, a neat and non-bulky oral inflation valve, a dump valve (as the above two had as well), and a circumferential reflective strip at the top. This thing feels bulletproof but it was almost as bulky as the DAN tube. It also had a few velcro straps that I had no need for so now they are past tense. I tied a bungee loop on the bottom webbing to hold everything when it is rolled, and these modifications have made it manageable to store either on the bottom of my backplate or in my wetsuit pocket. I use it for ocean diving and I would never do an ocean dive without some form of SMB. I also carry a whistle in my pocket (my
Storm) but I decided not to carry a mirror anymore and hopefully I won't be sorry for it. For SMB's, I favor the yellow color over the orange for visibility sake in the big blue, YMMV and there are opinions to either color.
So, that's it in a nutshell. I'd go with the DAN tube between it and the OMS. I am serious about diving and personal safety and that's why I upgraded to the Carter but again the DAN tube would be a good choice (I'd wish it came in yellow though). I hope this helps.
With kindest regards,
Thomas
