Onslaught, from what I gather from the product description, the threads themselves are not machined into the aluminum...they are steel coils inserted into the holes, like on some ARMS mounts...my gunsmith told me what they are called, but I forget...
I hope somebody chimes in on this, because these handguards could be just what the doctor ordered...basic, ventilated tubes with detachable rails just where you want them...On other stuff like the FF RAS, all those unused rail surfaces are just waiting to get dinged up and made unservicable...Phantom II's only real downfall, in my eyes, lies in its tubular design-no easy way to clean the barrel or de-gunkify it if it get filled up with debris...have to talk to the tube owners to see how they deal with the cleaning issue...
The only other thing out there (and it ain't REALLY out there yet!) that I think worthwhile is the URX...this has a removable bottom, sos you can clean the barrel easy...The LMT looks good also, but LOTSA bucks for that one!
By the way, the arument that the detachable rails would be easily lost is a "non starter"...there is so much crap hanging off rifles nowaday, the same would apply to ALL accessories...