Between the two of us our 3 boys are usually done within an hour. The eldest, 8 year old Golden, has become very lazy in his old age. When he wants to fuck its a fast deep knot, long cum, then he's finding his bed to lay down in. Our youngest, 4 year old Kelpie/Rottie has the stamina of a hearding dog and dominance of a guard dog. He fucks to breed and enjoys it. Will usually tie both of us, one after the other, sometimes more than once. Our middle boy, 6 year old Giant Schauzer Poodle, has gone through a glow up, learned the right techniques, and is now very keen on knotting. He's a biiiiiiig boy and if tied stays until he's completely spent. Sometimes good for a round two fairly quickly. I've had weekends by myself where I've been passed around between the 3 of them, mostly just the 2, on and off for a couple days.