Very much so. And if it fails, all you have to do is flip up BUIS and keep shooting.
Hey I just ordered on of these:
http://palmettostatearmory.com/1726.php
What do you think?
It looks okay, but I think you might be alble to get something a little bit cheaper if you build it yourself.
Not long ago, I think I saw some stripped lowers going for about $100. (Spikes Tactical, I think.) A standard lower parts kit usually sells for $50 to $75.
As for a stock, it depends on what you get.