Good positive sealing is definitely a must here. Not just to protect the electrical connections, but also to prevent ingress of air, water, sand, bugs, etc. So we'd want to do all of the things you mention if using one of those mounts. They really are attractive, IMO.
We get 80+ mph winds many times each winter at my house, and I live in a somewhat protected location shielded by a hill that is upwind blocking the prevailing wind direction. At my son's house, he recorded wind speeds well over 100mph on a regular basis before his anemometer self-destructed. Seriously, we've been looking to put a weather station in at work, but we will need to get some sort of professional-grade Mount Washington-rated system to get an anemometer that can handle the typical winter winds here.
On the hills where we have water tanks and radio/cell towers, it blows a lot harder. A few years ago, a cell tower blew over at one of our water tank sites. We happened to be there doing some maintenance on telemetry for that tank when the cell tower guys were there. They said that they had over 10,000 of those towers all over the US, and this was the first one they'd seen fail.
They said it had to be a defective weld, but we showed them that the failures were not at weld points, but out in the middle of the steel tubing near the base. The problem is that the relentless gusty winds simply caused the metal to fatigue from repeated, constant flexing.
They insisted that there was no problem and installed an identical tower.
That tower failed the following winter. It didn't just fall over, it snapped off and blew completely over the fence on the far side of the fenced-in tank site and ended up a few hundred feet away, partway down the other side of the hill. They then gave up on that location.
The freaking wasps here find the smallest of openings. Most outdoor electrical boxes, such as behind a motion light, outdoor electrical outlet or the like, have wasp nests inside when you open them up. You have to be careful!
With the PFA122, I don't need to use grease or wrap the connections. They're effectively the same as if they were indoors. And I like that because it makes rework, swapping, repairs, etc., easy.
The "front" seal is formed where the cable from the eyeball enters the box, made by the split rubber seal plug. The back of the box is sealed against the wall or soffit by some closed-cell foam, and therefore, the cavity in the box is effectively "inside of the building". You can use some RTV or other caulk to seal the back of the box against irregular surfaces if needed. The key feature is the rubber seal plug that squeezes down on the cable coming out of the camera body, and also seals into the hole in the front plate of the box. That plate seals to the box with a silicone rubber gasket. It's pretty snazzy as far as weather sealing goes.
With the PFA122, I can open the box without even removing the camera from its cover, and even after a few of our winters, the insides are pristine and dust free. From the connectors' point of view, they're in the same environment as all of my indoor connections. So I can disconnect and reconnect things without dealing with the tape or goo, or fear of wasps attacking me when I'm up on the ladder - well, at least from them coming out of that electrical box.
I get enough of needing to cut open, unwrap, and de-goo electrical connections working on radio systems up on towers or on high voltage connections for our 440V 3-phase motors, etc.
So when I can use an electrical enclosure setup that actually protects the connections so they don't need to be goo-ed and wrapped, I really do appreciate that.
But these boxes are big and chunky, for sure. It would be neat to have a mount like what you're using, but have the "sealed container" feature in which to make up the connections like we get with the PFA122 and similar boxes.
It seems like they could make a mount that looks like the PFV203W but give it the same rubber "stopper" as we get with the 122 and 121, and some sort of seal at the "building side" and that would be great. But it might have to be bulkier and defeat some of the good looks. For a rougher surface, you would still need the RTV or some thick closed-cell foam to conform and really make a tight seal at that interface with the wall or soffit, etc.
