I have a LaRue Stelth 18" barrel that I'm using for a light weight precision upper build.  Most of my lowers are Colt.  Is VLTOR still the go-to for the best precision upper?  I don't mind throwing money into this upper.  I don't need a forward assist or dust cover for that matter.  Recommend me a BCG too.  Thanks.

I'm happy with the VLTOR. Noveske is now selling the VLTOR MUR with the Noveske brand name on it. I think that in itself speaks to the quality. It is a forged upper but it's thicker and has been stress relieved, heat treated, aged twice and cryogenic treated. The drawback is that it is a little heavier than most but if you pair it up with one of their light weight hand guards, it makes up for it.

For BCG's, I like JP Rifles and Rubber City Armory. For light weight, JP has the light weight BCG and matching buffer. If you go that route, get it with the 5 pack of springs so you can tune the buffer to the rifle. You didn't mention gas block but if you're building a lightweight precision rifle you might want consider an adjustable. SLR and JP are my favorites. JP has a two piece adjustable with a detent that make it super easy to install and if you ever need to remove it you won't have to mess with your compensator.

You might consider a LaRue UU Kit.

I'm kind of likening this one.  Slick side, no dust cover.  Any of you familiar with this company?

https://www.cmttac.com/AR-15-Receivers/AR%2015%20CMT%20Billet%20Upper%20Receivers/slick%20side%20upper-ar15slicksideupper-upur3

Cross Machine and Tool builds very good stuff.

I had one of their handguards but I swapped it for some other gear to a buddy because I had no builds on the horizon at the time.  It was extremely well made.

Had a Stealth 18" upper.....sold it for a JP 20" upper. It shoots circles around the LaRue....not even close. Incredible accuracy with the JP....I'm amazed.

I use side chargers whenever possible. I like the right side reciprocating like an ak. Reduces blowback to the face exponentially with a can and easier to operate with a scope near the back of the receiver.