The fact that UTG IS and airsoft parts provider is scant assurance the handguards are quality aluminum, CNC to spec, or treated to a proper working hardness.
In fact, posts elsewhere by owners point out that their UTG handguards are soft aluminum, the rails not machined to spec, and won't hold up to carbine course work or tactical use.
No known builder or maker of AR's offers them as original equipment. Nuff said.
As for quad rails, they are past their prime years ago. Even then, very few needed 48" of rail to mount everything, and mounting everything is the worst thing to do with a combat carbine. Internet posers post pictures of there kitted out AR's with three times the money in lights and lasers than the gun is worth. Combat users have just one or two items.
These days, with consolidated light systems in a vertical grip, spending money for more than an add on rail is more than needed. To repeat a thought, it's not like someone is really going into combat with it.