I hear that that nylon/poly reins are generally not recommended because they tend to give rope burn in the event that anything causes them to be yanked through your hands rapidly.
I also hear a lot that split reins are generally best if you trail ride because sometimes your reins can get caught on something out on rough trail and it's better for you to lose a rein than for your horse to get caught tangled up by the mouth. Not something I'd ever thought of before I saw this mentioned here on the forum someplace so I'm switching over.
A lot of useful advice already. Really I'd go with whatever seems best to you (unless you show, in which case it would be best to go with what is standard for each discipline). Kind of get the feel for how the different styles, shapes, and materials fit in your hand and go with what feels right.
Personally I think I prefer leather/biothane split reins (for Western which is primary for me), not too long a length. I like them because they can be used almost just like a single loop rein but also have a lot of other options and also have the safety for trail mentioned above. Not to mention I just really like the look of them!
However for English riding of any kind, I've never seen anyone in anything but a shorter loop style, either braided, rubber, or plain, always flat, either leather, biothane, or leather/cotton combo. I never really see anybody riding English in any Western-style reins at all, and do personally own a set of those, too.
Last edited by rocky pony; 03-03-2011 at 06:10 AM.