If you go to a mono loop use 30 lb. test. The Perfection loop is absolutely the way to go. Any shop where you buy your line should do it for you. The only problem with loops is that they make a "hinge" point. I have gone to tying my own leaders using a nail knot to the fly line and blood knots for the leader with a surgeon's knot for the tippet. Besides not getting a loop caught in my front guide, this system really gets flies to turn over. It has made a huge difference in my casting.
To Miss Nancy - she hated fishing, but loved a fisherman.