On my 6.8 build i had originally decided to go with a Daniel defense barrel with pinned fsb. I have been rethinking going with a fsb and thinking of going with a 12" rail and flip sights. I was looking for a place that would pin a lp gas block, but not a lot of barrel makers will do it. How important is the pinning of the gas block under te hand guards?
Pinning is recommended for any hard use upper, but not required for a range plinker.
You can do it yourself.
We developed the MicroPin Gas Block with specific features to allow end users with basic equipment to sucessfully secure their gas blocks, with results similar to factory pinned offerings.
http://www.blackrivertactical.com/concrete5/micropin-gas-block/