I've been using Time Impact pedals for many years and they are good and they last & last but it's getting very difficult & expensive to get cleats for them now. So, I'm thinking of changing to Speedplays. I understand Speedplay offer 3-hole & 4-hole cleats but the 3-hole version ends up with a "taller" stack-height? Is that right? I like a low stack-height - so is it better to use the 4-hole cleats with Speedplay? If so, any recommendations on shoes with 4-hole fitting options? For shoes, I've tried Sidis, Bont, Nike .. etc and I really like Time shoes as they have a high heel-lift but I don't think they offer 4-hole options.