Wilson barrel and del-ton Question

[stickyfingers]

Can anyone vouch for the quality of the Wilson barrel del-ton uses in its generic rifle kit build? Do any popular AR manufacturers use them?

What about the flattop upper? It just says "standard flattop upper". Could I lose durability/reliability/accuracy by using this? Do popular AR manufacturers use a similar generic upper, or do they have their own?

And one last question .. The breach face/throat, (Where the bolt locks into when it is forward), is that part of the barrel or part of the upper?

Thanks in advance !
sticky

[gatsby]

Del-ton kits are one of the best deals out there right now. I have the 16 inch m4 profile upper with a chrome lined barrel (a must! :) ). The flattop upper is nice and it costs no more to get the flat top with t marks. Its very reliable being that its clean most of the time and i dont baby it. Great stuff, I can vouch for quality.
-dave