Will RRA ever make a compleat upper or rifle with a 4150 chrome lined barrel or don't they care what thier customers want ? how hard is it for them to get barrels?

I think you mean 4150 steel chrome-lined.  RRA most likely contracts out the barrels from Wilson Arms, as do a lot of the manufacturers nowadays, and 4140 steel is what Wilson uses.  RRA does have a few types of chrome lined barrels, I believe they offer the M4 and R4 (M4 heavey under handguards type) in chrome lined if you look around.  According to the Adco Firearms site a chrome lined midlength will be available soon.

From my observations, it would appear that many manufacturers are going over to chrome lined due to consumer request for it.  In the last year most everyone can get chrome lined M4 barrels now, and I bet it won't be long before 20" hbars come chrome lined.  As for the stel type, I wouldn't hold your breath as probably 95% of people do not know that it is a different type of steel, much less what the difference is between 4140 and 4150.

Now if we can just get them to offer 1/7 twist...

They have been available in the past, but very hard to find.  I managed to find one (and only one) that Pete in NH had, and I bought it.  It's currently at KKF getting a weight reduction.

I called RRA before about them, and they said they had to order 100 at a time, and they only had chrome lined mid-length barrels for specific LE contracts, then offered the leftovers to the public.

Sounds like from what you posted that maybe they're about to change that policy and keep them on hand... One can hope.