Here is my subjective opinion of the Odyssey + for use in IL2. Up to this point I have been using a Rift.
I'll start with the visuals.
It is definitely an improvement over the Rift, though not as great as I had hoped. Screen is clearer and colours are much deeper. I actually find it brighter than the rift. Not sure if people who think it is dark are being thrown off by the lack of light screen door effect that washes out everything or the deeper blacks but it is plenty bright. The screen door effect is pretty much entirely gone. You can still make out the pixels same as you can on say a 720p monitor, but they are very small and there isn't the obvious gap (screen door effect) between pixels that you saw on older VR units. Spotting is improved as the increased resolution and lack of screen door effect lets you pick out small contacts more easily and I would even say my situational awareness has gotten a boost as re-acquiring contacts that I have looked away from and come back to find is easier. The sweet spot is noticeably smaller than the rift and I wish the lenses were of a different design that improved this. You do have to more purposely look directly with your head at things that you want to see with perfect clarity like text and gauges. However, I would argue that a lot of the stuff that is outside of the odyssey's sweet spot has almost the same clarity to my eyes as things that were in the larger sweet spot of the rift. I do enjoy the deeper colours and everything looks much more vivid. Another drawback though is that the WMR built in ASW type tech is not as good as the rift at smoothing motion. Planes zooming around in the periphery have more ghosting and chromatic aberrations. However looking directly at them resolves most of this. I'm currently running mine at 190 SS to get a crisp image that is approximate to the resolution of 100 SS on a Vive Pro. (The way Steam VR handles SS is different depending on headset) Without turning it up from 100, my Odyssey + would be running at almost the same resolution as the rift runs at 100 SS.
This thing is definitely not as comfortable as the Rift. Like a previous review. I thought when I put that headset on without it turned on, that there would be light leak from everywhere. Somehow, with it on, the light from the unit drowns out any light leakage and I do not perceive any, even from the bottom. With the halo pulled down the back of my head, which is how I've been wearing it, it is fairly comfortable at first. However, after about an hour, I find that there is pressure on my forehead that makes me feel almost as though I have a minor tension headache coming on. I think this could be vastly improved with a thicker foam face piece from VR covers once they develop one. Here's a big drawback for some people, the minimum IPD as reported by the WMR software for the unit is 63mm. My own measured IPD is 61mm and I find somewhere around the very bottom of the adjustment it feels the most clear. I'm uncertain if a little bit more downward range would help my visuals as I actually run it a touch off the minimum stop. However for people with significantly smaller IPD this is a problem and would likely make the unit unusable. I'm honestly thinking this is the major problem for most of the people complaining about a blurry image. How Samsung thought making the adjustable IPD range 63mm to 72mm was acceptable when the average IPD is 63 is beyond me. Otherwise, the unit is relatively comfortable. It's a bit disappointing that such simple issues were overlooked that could have really made the Odyssey + a home-run.
This is the final part of the unit I wanted to address, as someone who has an education in audio engineering and runs a home recording studio. Ya, the built in AKG headphones are not incredible, but honestly, I don't think they are any worse than the Rift in terms of quality. They are a decent pair of budget headphones with decent sensitivity and range... however, what they lack is low end. I simply ran a system wide EQ called Equalizer apo and rolled on more low end in a shelf with a gentle slope starting at 400 hz down to 20 hz. (Peak is about 6db) The amount I added would likely make the headphones a bit boomy and have some loss of clarity for regular listening and a more appropriate amount for this would likely be approx a 3db boost. However I find that the 6db low end shelf gives a close approximation of the muffled boom and tone of the engine and other sounds that a pilot would hear with a ww2 era headset on. Works great for me. Again, disappointing that between AKG and Samsung, they could have picked a flatter sounding headphone to begin with.
Overall, even with these annoyances and requirements for user intervention.... I think given the price, the odyssey + is the best VR headset going for IL2 right now. Sure if you want to spend more money you might be happier with a vive pro with gear VR lenses, but you'd be giving up the lack of SDE for a bit larger sweet spot. However if you have a small IPD, I would recommend you avoid it.
Hope this helps people who are weighing their options.