dog,
I've always had some difficulty acquiring a target fast with any kind of peep, but I do feel they are a more accurate sight system than an open sight. I prefer a shallow V and small bead with a flip twilight bead.

Personal choice enters into this question in a big way, IMO. I'd go to a large gun shop that has a big used inventory and try out everything there, before making a decision as permanent as you need to make.