I know freefloat vs regular makes a difference. But once you are in freefloat territory, does it matter if you aren't hanging anything on the gun?
in otherwords, does a 50 dollar tube work less well for accuracy than the 350 dollar ones I see? or the 150?

I am not sure what the benefit is between the two as long as everything fits from an accuracy perspective.

I get it if I am hanging stuff on it, or mouting something to it for deflection, but if it doesn't touch the barrel does it matter?

I haven't bothered to try a set of UTG Pro drop-in rails on my DCM tube.

Anytime you disassemble and reassemble there's a good chance of a change in group size or POI.

Unless the handguard attaches to the receiver, it's still contacting the barrel via the nut. How much does this impact groups? Not enough to worry about unless your goal is "screamers" (<0.100" @100yds).

The expensive ones are more refined and sometimes have more features, or may serve a niche market (Geissele MK7 NM). Cheaper ones may need some fitting and extra care during assembly, and might not be as durable.

I guess that is part of the question. durable how?

as long as the barrel nut doesn't give, I am really only using the handguard to cover the gas tube and rest on sand bags.

Thanks for your response.
Had to look up DCM and that is kind of interesting too.

I switched from a thin one to a URX4. Larger ID for room for the gas block to whip around during recoil. Also one piece with no separate barrel nut. Maybe a tiny increase in accuracy although my main purpose was for the Mlok slots.

I have never heard of one without a seperate barrel nut.
how do you time the whole handguard?
do you have a link to one?