I have 3 atlas s ones on different rigs and really do like them, and the attachment method. I don't beat them up so can't comment on overall durability, but they sure are nice to time and install. Profile is great - assuming your gas block fits. I did have one gas block I had to return because it was a bit fat. That being said, my theory is "weight is a bit subjective". For example, I have a 3 gun rig that is pretty light - stretch 16 barrel with JP comp, Light Handguard, JP lightweight bcg, taccom buffer setup etc. Then another that is actually a full pound heavier with a pretty burly handguard, same fluted barrel length and profile, no muzzle device. Everyone who shoots them comments on how light the "heavy" on is - It's always surprising because I spent so much making one light and it's not that gets the comments - but I think it is weight out front. In 3 gun I don't know you need light overall as much as super fast handling, which is at the end of the day balance. I won't, but I assume if I took the JP off the stretch 16 it would noticeably change the ergos and make that rig feel light.
All that to say, I echo the barrel nut weight being fine to play with if it makes you feel better or you are really looking for a certain threshold, but if you're looking to invest you could hunt down a titanium comp and even gas block and save just a couple ounces at the point where it matters the absolute most for quick transitions. Just my $.02