Hey, a bit late to the party. Been drowned in Skyrim since I just finished my 5x1P about a month ago. (Thanks Helifax for getting a fix out for me so fast!) Yes, you lose some FOV. But it's not that big of a deal because the lack of centered interfaces in most games means that the outer edges tended to be ignored and give you more missing information. But the real quality of 5x1P is your added vertical. When gaming on a 3x1L, I couldn't help but feel that I was looking out of a bunker or something. Sure, I had a nice and wide view, but there was nothing top to bottom. 5x1P is "less extreme" (hah) in this regard. It's far more immersive and I feel as if the side vission is actually used. And for your earlier figure, with bezel correction it's about 1.7 times wider than a traditional widescreen. So, it still beats the crap out of gaming on a single 16:9 screen, no matter how huge.
But, again, the most important factor here is immersion.
Though, there is one little benefit. It's a lot easier to move into 3x1P, which works without hacks on far more games (in my experience) so you have a bit more compatibility out of the box. You can also curve the screens more gently than 3x1L but still get that wraparound effect.
Sure, it's not perfect and the advantages really lie in what your preferences are. I'm a fan of Human interface devices and immersion, so the move to 5x1P was natural for me. If you're in the "hardcore gamer" crowd, you'd prefer the wider FOV. As well, if 3D is something you desire, 3x1L will also be more up your alley. Having messed around extensively with 3x1L, 3x1P, and 5x1P, I'm going to say that each has their tradeoffs. But at least with 5x1P, you also get 3x1P. Though, you also lose 1x1L for those games with super finicky resolution requirements, like GTA 3. I guess that's what windowed mode is for, though. ;)
Also, Skyrim is amazing on 5x1P. ;) I'm so glad I waited until it was finished to play.
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