If I could only have one it would be an Ar-15, that being said though I have owned a couple mini-14's and a mini-30 and have never had any problems with reliability. I currently own the new mini-14 and like it a lot. The sights have been improved IMO and the rifle shoulders great for me.
For quick handling I would grab the mini
For 100% reliability and ease of take down I would grab my Colt AR.
