I was thinking of building an AR totally from scratch however, after adding up all the bits and pieces, it seems to be a little more cost effective to buy a complete upper and build a lower. I am leaning towards the White Oak .223 varmit upper. I have read good things about them. It will be 18 in. bbl rifle lenghth gas sys. and 1-7 twist. Cost is $613.00 shipped. Thought this is a good price. My funds are limited to under $1000.00. Any thoughts on this upper?