Personally I wouldn't put a youngster in a Pelham, and I wouldn't use a Pelham for the issues you've mentioned - Sorry. I'd look at training and getting a good instructor to help.
With regards to the bit as a product, I really like NS bits. I have the Slimma mouthpiece on a Weymouth as part of a double bridle on my Advanced dressage mare in which she goes really well in.
I was told it's much milder than the NS waterford that I have in now, its not a double bit but it has the double effect. She's 6 years old so not young young and I'm only using it for show ring. I am looking into having some lessons.
