Samsung 27" curved screen freesync monitor here.
I like it, and coming from a small 20" monitor it was a world of difference.
Wanting to add 2 more of them for triples, but it'll have to wait for now.
My main issue with a single monitor is peripheral view. I struggle, at times, to see my blind spots.
Head trackers cause too much movement for me. Not a motion sickness issue as much as losing ability to focus on the motions of the car (which are relied on in sim racing, obviously, since we are missing ass in seat and all feel that comes with it)
IMO, VR is the future of sim racing, especially.
Triples can never replicate a true 1:1 scaled environment.
But, as Alberto said, there are issues to be overcome. Some in the hardware itself (inside VR you cannot see your physical wheel/shifter/other stuffs, so have to go at it blind) and some with the users (motion sickness in VR is a game breaker for some. Others say you just have to go at it slow and get your "legs"...small intervals of time in the beginning, then longer)
VR, even at lowered resolutions is fairly heavy in terms of hardware usage, so you're going to need to make sure your machine is able to pump it out efficiently.
Resolutions are improving, but it'll be a while still, I think.
Matter of personal opinion and what one feels gives them the most immersive experience, really.
But, I foresee a future where VR in sim racing is the norm.
I'd love to give it a go, even now. Sadly, I live in the middle of nowhere, literally a few hundred miles from anything resembling such a place to test such a thing. And, funds are a bit short for all the gear required to test it for myself at this time. Meh, maybe someday.
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Proud 2017 Indy 500 Rookie of the Year