What color Kool-aid? Or do you use red for O2 and purple for 50%?
Green apple kool-aid, of course. It works great for oxygen.
I think this is a new scubaboard record 16 replies and only one actually on topic.
Not to be blunt but you're asking the wrong questions. It seems neither regulator fits your self-imposed criteria.
Both regulators will work fine with pure oxygen. They are functionally the same regulator with some minor design modifications (fanboys will argue differently but ultimately they're both balanced diagrams first stages from the same factory and the second stage designs are also remarkably similar). There is maybe slightly better QA in one of the brands.
You said it yourself you cant get the green face plate for the Deep 6 Excursion and it's not "rated" for higher O2. If you want to stick strictly to manufacturer guidelines then I'm not sure either will work. If you don't care about that then get the Deep 6 Excursion and buy some green spray paint or green duct tape. I'm joking..
At one point HOG only "certified" their regulators to 80% at 3000psi or 2400psi with 100% O2. I have no idea if this is still the current recommendation but here is what Chris Richardson (formerly of HOG and and now Deep 6) has to say on the subject..
The reg isn't "almost" O2 clean, it is clean to 2400 psi with 100 O2.
The limits are placed because the reality is that NO scuba regulators are designed for use with 100% O2 at 3000 psi, some may be willing to take the risk of selling them as Oxygen Clean without pressure considerations, I'm not. Think of the medical oxygen market, they would LOVE to use higher pressures than 2400 but they don't. The risk reward calculation is to much risk for the reward.
The other reason is I believe in EDUCATION, many people will believe that a O2 clean reg is perfectly safe to use with high pressure oxygen because the manuf markets it so, the risk when using 3000 psi of Oxygen in a scuba regulator are quite high, even when you do "everything right" , you should be aware of that.
Plus as pointed out, when you need more than the 2400 psi will give you a bigger bottle isn't a issue at all.
A GREAT many of us have repeatedly broken that recommendation and used different brand regs with pure O2 at 3000psi+ Will it come back to bite us in the ass? Yes, no, maybe? All you can do is try to mitigate the risk and figure out what your acceptable level of risk is.
For the record I have nothing against green second stages on an oxygen regulator. I dove with a black second stage on my oxygen bottle regulator for 10 years and didn't die. My current one just happens to be green because I got it cheap and it worked. I have no qualms about throwing any of my other stage regulators on my oxygen bottle. It's not something I rely on for gas verification. If this one becomes unrepairable then I'll probably switch it back to a black one so it matches every other stage regulator that I own so it's interchangeable.
While I can certainly throw a green regulator on any of my other stage bottles it just feels "wrong" to me so I keep it dedicated to an O2 bottle. What happens if your green O2 reg fails? Are you going to skip the dive because the only other regulator you have has a black faceplate?
I would not require this for class nor would I agree with an instructor for requiring it. If they want to make it a recommendation that's certainly up to them. Many people already alluded to why they think it's a dumb requirement.
