The H2 buffer is all I use now that I'm controlling the gas with my patented modular gas block.
Unlike the two you mentioned above, my gas block uses an unmodified gas tube and since it is modular, you can swap plates to accommodate any caliber or gas system.
Below is a picture of our custom 3 position plate where you can have a shut off or drill it out to make it whatever you want. I prefer to set mine up so that the left is optimal unsuppressed, middle is suppressed and right matches the port in the barrel which is adverse since just about every barrel out there is overgassed since barrel manufacturers know people are going to run the cheapest stuff they can.
When it gets hot, you can just push the regulator with the tip of a
bullet or something similar to move the regulator. No special tools or
Video showing the regulator doesn't get stuck after heavy full auto fire from nasty, corrosive 5.45 ammo suppressed:
Here is another video at hi speed (480FPS) showing the difference between regulated and non-regulated full auto suppressed on a 10.5" barrel. H2 buffers are used in both videos. Ammo is LC M855 and you'll see that the unregulated is firing faster (approximately 200 RPM faster) the regulated one fires 3 rounds after the unregulated is out.
You barely see any gas coming out of the regulated one. Note that you will still get gas coming out of the bore/chamber but it will be greatly reduced once you regulate the gas. Recoil will be reduced and you will get more rounds downrange before you have to clean. Also note, some ammo is more gassy than others. PMC is definitely more gassy than LC even though LC is much hotter.
Another video of the same 10.5" upper in real time and you can clearly see the absence of gas once regulated:
More info, pics and videos on my site: http://micromoa.com