I am looking for a 5.56-.223 riffle to keep in my truck for varmints. I went to my LGS and saw a 16" flat top DPMS ar for $589. While i was checking it out i saw something new, well to me at least. A kel tec su-16c $535. I've been researching the kel tec and am honestly impressed by what i've read. So i am wondering what your opinions of them are and which is the best buy?