Is there any reason you can't use the vdh wing as strictly oral inflate? Maybe put a rubber cap on the lp connection to protect the inflator valve?
You can orally inflate a wing just as easily as a horse collar.
We have one friend that that dives an Argonaut Kraken and he often wears a wing with his VDH plate, but he never uses an LP hose for the inflator. He doesn’t think an LP inflator is worth the hassle of one extra hose.
The horse collars also requires a LP inflator or you will have to orally inflate it unless you get a Frenzy (brand/model of a vintage horse collar which came with a small tank and regulator). They are fairly rare, esp if the tank is with it. So unless you just want a HC, you might as well just orally inflate the wing .
The Fenzy has a small high pressure air cylinder, but no regulator. The diver just opens the valve slowly to control the amount of air into the horse collar.
If you look at my avatar you will see a pictures from the early 70’s with my old Fenzy and the second picture is from about 15 years ago (with a different Fenzy). My old Fenzy is tired and it leaks now.
Note: the Fenzy in the two pictures in the avatar is not the same, but the Royal Aqua Master regulator and the Farallon snorkel is the same.
I agree with the suggestions to use a wing instead of a horse collar. All horse collars will put some air behind your neck (the highest point) and not only affect your trim, but some will actually even push a bit on the back of your neck. The Fenzy in particular has a huge volume of air behind the neck. I always thought it was great for surface flotation, but awful as a BC. When I started using the Fenzy, there were no actual good BC available, so I didn’t know any better.
If you still want a horse collar, I would recommend a Seatech or similar (with small volume behind the neck).
A Fenzy would be expensive and a terrible BC… but the cool factor is its only redeeming value. Don’t ask me why it is cool… it just is. It was the first to have any air source.
Note: The Fenzy in the two pictures is not the same one, but the Royal Aqua Master regulator and the Farallon snorkel is the same.