On the eve of my Aimpoint purchase I’ve begun to think of BUIS options, a fixed or folder. I do not plan to run a magnifier so I believe either would work. What are your thoughts, preferences? I’ve read that some people found the fixed to take a little more shooting to get used to looking through or past it. What are your thoughts? I’ve not used one so I can’t say.
At this point I’m leaning toward a Troy if folding or a Larue if going with the fixed. Thanks
I would go with a flip up. You can make a flip up a fixed just by leaving it up. 
C4
While having a fixed sight in the way kinda bugs you when you’re just fiddling with it, once you get shooting you stop caring.
After having had both I’m going back to fixed just for simplicity’s sake.
Flip
Leave em up until the optic turns on, then you can put them down.
Once you get used to a fixed you won’t know it’s there till you need it and it’s already to go. There’s also nothing wrong with a quality folding sight like a Troy or KAC. Should you change optics there’s less possibility of an obstruction. There’s definitely something wrong with some of the cheaper quality folding offerings that go up and down while shooting. The ones you tear off in frustration and buy Troy you should have got in the first place…
The only optic that I have that turns off is my SD. You gotta love Aimpoint battery life.
Thanks for the replies. I’m going to be using the existing fixed front sight. Either rear sight I mentioned should work fine with that, shouldn’t they?
The Troy & LT are my favorites, but the LMT fixed rear should be a consideration as well depending on your needs.
Also, GG&G make a flip up with adjustable windage if that’s another requirement for you.
Both are good, but with the LMT you will not have the option to lay it down when using an optic. With a flip you’ll have the best of both worlds, a fixed rear, and no-rear when running an optic.
Also consider the ARMS #40L series. They are pretty solid and don’t “lock” up, as the spring keeps them up. This way snagging them or hitting them isn’t going to hurt the pivot or the sight. The ARMS will not stay down until you pull the release backwards and press the sight down underneath it.