Hi - Still in the learning phase of potentially showing my sheltie. I will be heading to a Shetland Sheepdog dog show in a few week to take lots of notes, ask a lot of questions, perhaps even be allowed to film a handler or two prepping the dog for show... I also am getting the 'stuff' gathered to begin training with my puppy, but have a newbie question: which collar should I use to train my puppy? I keep my dogs collarless when home, but when we head out, the two older dogs wear martingales and we used to keep our late Sheltie in a chest harness since his 'collapsed trachea' plus his thick ruff meant he could slip out of any collar in a second. We plan to keep the puppy in harnesses for the exact same reason (plus he's a wiggle worm) I see a lot of shelties wearing chain collars in the ring and was wondering if this would be a good training (for showring only) collar for Kelby? I also see some martingales as well as resco (?) collars. Any preferences?