I'm getting ready to build my first mid-length upper. Right now I'm looking at RRA and Armalite barrels. From the picture on Armalite's web-site, it appears that the Armalite barrel has a slightly lighter profile than the RRA. Is this correct?

I imagine that these are both good barrels. Is there any reason to go with one over the other? Are there any other good choices for a mid-length, 1:9 chrome-lined barrel?

Thanks for your replies!

I have owned both personally...  

The Armalite barrel is definitely a slimmer profile.  It's not as thin as the government profile, but the RRA barrel is a full, non-tapered HBAR all the way to the gas block!  It's unreasonably heavy in my opinion.  

The RRA barrels do have a chrome lined option (sometimes), but I'd definitely go with chrome lined unless $$$ was an issue.

If you go with RRA, check with ADCO as they offer the profiling option for just a little more $$.

At the time I was building mine (about three years ago), RRA and Armalite were the ONLY games in town.  I didn't keep the Armalite because it was a complete upper, and all I wanted was the barrel.  I kept the Rock River, BUT I sent it to Kurt's Kustom to have it turned and fluted.  It now weighs about the same as a medium profile barrel, but it cost me nearly $300 for the barrel and work.  I also ended up buying one from ADCO with the profiled option (ADCO started offering them about TWO WEEKS after I sent mine to KKF) with the intention of selling my heavier fluted one, but nobody else was interested in it either :)  Every time I mentioned having the two barrels, I'd get "the fluted one's nice, but how much for the ADCO barrel?"  

PERSONALLY though, if I were just now building a mid-length, I'd look long and hard at the Sabre Defense mid-length barrels.  They are already government profile, and will cost about the same as the other two barrels.

"Unreasonably heavy" is a good way to describe the RRA barrel. I had mine turned down by ADCO. +1 for the Sabre barrel. Thats what I would use if I were looking for a midlength.