https://i.imgsafe.org/b713631f23.jpg ----- https://i.imgsafe.org/2f17186093.jpg

Trying to decide between a 11 or 13.5 inch Noveske NSR Handguard. Any other suggestions would also be great.

Build List
Noveske 16 inch SS Recon Barrel
Noveske Marked MUR Upper Receiverr
Noveske Marked M16 RCA Black Nitride Bolt Car
Noveske Super Badass Charging Handle - 5.56rier Group
Surefire - WARCOMP Flash Hider - 5.56 - 1/2x28
Talon Ambidextrous Safety Selectror
Battle Arms Enhanced Pin Set
Geissele SD-C or Super Tricon (I have a couple SD-Cs already but am thinking about trying the Super Tricon)

Stock & Grip are undecided

Another question that someone might be able to give insight on is, what would be the best way to go about darkening up the SS barrel? Noveske SS Barrels have a bead blasted finish.

I would definitely go with the 13.5 vs an 11.  An 11" handguard will barely, or not completely, cover the gas block on a midlength gas barrel.

As far as blackening a stainless barrel, there are numerous options, such as:
Black oxide - industrial process, probably done by a specialty shop
Cerakote - numerous small companies do cerakote color coating now, seems to be a good process
Moly Resin - if you're dedicated you could DIY this
Krylon - easy, fast, cheap, will get damaged easily and then it's easy and cheap to touch up

Depending on your budget and logistics of where to have it done I'd probably suggest Cerakote.

I am going with the 13.5 inch handguard for sure now. I'm in Nevada and there are a couple good Cerakote shops but the lead times at the good one are around 8 weeks. I think I'll run as is bang it up and then just have the whole thing Cerakoted

Those Noveske stainless barrels are so pretty bead blasted though, shame to get it dinged up before finishing.

I totally agree! I am hoping only the lower, upper and rail gets banged up and then I'll just get them all coated along with the barrel at the same time

Agreed, I always thought the bead blasted Noveske's looked really good (I have a shiny stainless 16" MRP barrel I want to bead blast like that).  It isn't like they'll reflect light either, they'll blend in in the field.