I just assembled the same set-up on an ICS M4. I opted to use the stock outer barrel, but that required a little modification with a dremel and a file. I used the type "B" flip-up sight (also King Arms) so it would allow me some lateral play to set the sight up.
There is virtually no change in weight distribution of the gun as this MRE is very lightweight.
For those interested in this rail system, get a quality one-piece outer barrel and a type "A" flip-up sight (drive-in pins) instead of the type "B" (screws) sight, unless you have the urge to break out the dremel.
Nice review, btw.
Age verifier Northern Alberta
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Freedom is the wolves limping away while the sheep reloads.
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