I'm looking at an Aero Precision 10" upper in 300 BO, but I can't decide between the S-ONE handguard or the R-One.

Any thoughts on either of them?

A shop in Tacoma right by work, and right by where Aero is/was located has a whole bin full of them. I got to handle both examples a few weeks ago and what struck me was how incredibly light they are. If you want, I can stop in there on the way home today if there’s anything more specific you’re curious about. Not attached to rifles and no more experience than handling and observing, but up to you. Aero makes quality stuff, I don’t think you can go wrong with either, just pick the one that has features you prefer.

Thanks, but that's not necessary. I'm just curious what everyone has to say about them.

R for me I do not like the split rail of the S.

I like the S-One. No top rail in the middle where you're gripping it to chew up your fingers, and it has a very lightweight and svelte profile that is easy to get your hand around. If you need a few more rail segments to mount something to, it's M-Lock so It's easy to add them.

If I were going to hang a bunch of stuff off the gun and needed the full top rail, I'd definitely consider the R-One, but I like a lighter, less-cluttered setup, and for my purposes the S-One is my favorite.

I also really like the mounting solution that Aero uses for their handguards...they have a triangular locking nut that interfaces with a corresponding groove in the barrel nut. It give the impression of being much more positive and durable than some of the other alternatives out there, particularly the friction clamp-on styles.