It's a completely personal thing. Try to find someone similar in size to yourself and see if you like the feel of theirs. Otherwise you can spend a lot of $$ going through many different ones. Ask me how I know...... ; )
I'm looking at these. I hear they are not avail until Jan 10 though. FBI has a version out as well.
I'm not tall (5'9) so reaching the crash bars are difficult and it should keep it cleaner.
If your short, 5'9-10" the HD 360 peg mounts work great, I mounted them down low at an angle off the front of the boards. I can slid my feet forward on the boards and rest the ***** of my feet on the pegs or if I want to stretch my legs out straight, I put my heels up on the pegs. Regular highway pegs up midway on the engine guard are too long a stretch for me, I'm 5'10".