Leapfrog, you have taken this from silly to ridiculous.
If you go in for argument, take care of your temper. Your logic, if you have any, will take care of itself.
The question from the OP was understandable. Newbies ask such questions. Part of the discussion that followed was a demonstration of nothing more than speculation and nonsense.
Opinions are formed in a process of open discussion and public debate, and where no opportunity for the forming of opinions exists, there may be moods of the masses and moods of individuals, the latter no less fickle and unreliable than the former but no opinion.
Yes, fifty years ago is relevant but apparently, you have learned nothing from history.
Fifty years ago Aeris didn't even exist. Read the OP.
If divers, using fifty year old technology, could make dives to 300-400 fsw on AIR, what do you think that modern equipment is designed for, 130 feet?
Manufacturer's specification and CE, ISO and other standards exist to guarantee the safest possible use of products, in this case scuba diving regulators that in decompression model diving are the divers key life support system. The point about equipment that was used 50 years ago remains moot. The question is what is best equipment available today.
If so, why do you think the OEM's are constantly advertising high flow rates and low WOB? What do you think those monster, 8 inch, 130 cf tanks are for?
Straw Man argument. If a manufacturer says a product should not be used beyond 165ft and another manufacturer says their product can be used at a greater depth and in both cases the product conforms to the relevant standards, there's not much room for discussion.
Manufacturers know that tech divers, commercial divers, NASA, the Navy and others will occasionally need to use their equipment to go far below 130 feet.
There are specific products for each of those groups. The Navy publishes a regularly updated ANU list. It also specifies in what conditions of temperature and depth the regulators can be used. Scubapro has products on that list. Excellent products. However, diving in the Navy, whether it be for salvage or combat is far removed from Tec Rec which is the activity the OP wants to participate in. The Navy specifically authorises the use of the the G250 with the Mk.10 (no longer manufactured) and the S600/Mk.25 for use to 190 ft but NOT in COLD WATER. Read the OP.
Almost any brand name regulator including mid price range models; you name it: Aqualung, Apeks, Oceanic, Scubapro, Genesis, Mares, etc can be used at helium depths.
That's your opinion. It may be a valid one but one thing is
can be used and another thing
is designed for use.
That would be true even if He did not have a low gram molecular (atomic) weight (clever argument that and techies know that helium has lower flow resistance).
I was not aware that the OP was looking for a disertation on the atomic weight of gases used in technical diving. I obviously missed something and stand corrected.
BTW, that is how an instructor should talk.
DIR and Hogarthian phiosophy works well under the water. On a forum designed to encourage the freedom of speech and to contrast legitimate opinions, it's tantamount to National Socialism. Now there is
"a way instructor's should talk?" What are you going to do with the instructors who don't talk the way you would like us to talk? Send us all to a virtual concentration camp?
Leapfrog, how the heck did you get to be an instructor??
Just like every other instructor who is certified by the agency I am affiliated with. The process is in the public domain and it would be off topic to enlighten you as to the procedure here.