Ho boy so basically you've tried everything I've thought of testing myself, and you hate them all. Not so optimistic for me!
I've always dived rental jackets with one cambands. What I hate the most is lifting the bc over the tank. I also dislike closing the plastic buckle, but that part of the pain is quick.
I'm putting together my first personal set of harness, soft plate and wing. I will always be able to wet everything anytime I want, tropical boat diving only.
I'm taking all of your advice into consideration. I wonder if our differences in comfort preference and diving conditions would mean the best solutions for each of us might differ. Or perhaps all the cambands I've used are crappy plastic rental stuff, and I might not hate better cambands and ss buckles. Hm...
Your experience may vary from mine, so there is no harm in buying QD cam straps and seeing how they work for you and how much you like them. Worse case scenario is you post them on SB and sell them at a slight loss.
I have not used metal cam straps, other than the QD type you pictured, and have never had any issues with the plastic ones I have used...except for the overly stiff and slick webbing ones we got from Dolphin Scuba (a little too short, a little too stiff, and a little too slick)...but that is/was a webbing issue not an actual plastic cam issue.
Be careful what you wish for as you mentioned the pain of closing the plastic buckles is quick. I don't know if you mean that figuratively or literally. What I do know is that with QD cam straps it is very possible to get your fingers pinched by the metal buckle. Although it has not happened to me, I was aware of the possibility every time I set up my gear. There was a warning/explanation on the Dive Gear Express web page when they were selling QD cam straps that explained that one should close the buckle with a flat palm as if one had wet nail polish on and was keeping their nails from touching anything and getting wrecked.
A little bit more expensive are the Highland QD tank straps that work as a normal cam strap or QD...I wish I tried these when I was experimenting but at the time I did not want to spend that much money:
Highland Tank Straps, w/ Quick Release Cam Buckle (PAIR) | Dive Gear Express®
Also, Aqualung makes a QD camstrap similar to the OTG ones you linked to but they have a mechanism that keeps them from pinching closed on ones fingers...I don't know how much they cost in the US but they are pricey here in Europe and AL stuff tends to be less expensive here (I think one shope quoted me about 70euros per strap):
Griplock Tank Band Assembly | BCD Accessories | Aqua Lung
Good luck with whatever you choose to do...post back your experience with whatever product you purchase.
Cheers,
-Z