I have Dr Cooks for my two. At risk of boring people again, here is what I wrote:
Yes I use them. I have a 13 yo ex RS gelding who was ridden in a Pelham, because he was 'strong' and 'naughty'. No, he just didn't like heavy handed beginners hauling on his mouth and said so. He's been in Dr C since I bought him three years ago. We hack, jump and school in it, never a problem with brakes or steering.
I bought a recently broken five year old Anglo Arab and put him straight into a Dr C and he is doing fine. Shook his head a bit to start with - but then he used to chomp endlessly on the snaffle I had to use fo a week before the Dr C arrived form USA. He is quite happy now and very responsive.
I am terrified of my heavy hands and find I can ride and be more relaxed knowing I am not ever going to jag the horse in the mouth. I have used them on three of my friends horses (because of my hands issue) and they have all settled well to them, including a mare who was said to be a nutter and that I would die riding her 'without brakes'.
So, yeah, I like them. They are not suitable for all horses or all riders, but they do for me
Thanks ChicoMio. That's interesting. Did you find it easy to get used to it after riding with a bit? One of my chaps has cut his mouth (don't ask - it always amazes me that horses can do things you wouldn't think possible) so I'm going to have to rest his mouth while it heals. I'd rather not have to stop riding so am looking for something to use in the interim.
i have one but as i want to do dressage unfortunately i have to ride her in a bit. but used it for hacking, jumping and fun rides and prefered it to a bit in those circumstances - now she has navicular we only work in an arena so its gathering dust - may come out next yr if lucky to have soft enough ground to hack