Bit help!

[iloveCharlie5]

My gelding is fantastic in the school; he goes well on the bit, in a lovely outline, although it took a lot of schooling to get him like that! He gets a bit strong sometimes, not dangerous or bolting, just a bit heavy on the hands.
When we hack out, in certain circumstances he can get quite strong, and I am quite little.
Once or twice he has put his head down and It takes a lot of work to pull him up. He does it because the horses we hack out with are much bigger and faster than him, and he doesnt like being left behind. I always feel embarrassed to ask if I can go in the front because then I feel bad for the other girls; two of the horses are extremely strong, and very big, so I feel bad that they are getting their arms pulled out behind me whilst I am cantering happily in front.
I wanted something quite mild (he goes in a Kimberwick at the moment) and nothing too harsh on his mouth as when we are in the school he is quite light in the mouth. Also, I wouldn't like anything too complicated to use, as I am fairly new to the world of horse ownership (he is my first horse). My instructor recommended a Pelham, as she said this was a lot like the bit he has in now, it wouldn't be too harsh on his mouth, and it would provide a bit more control. Could you give me any advice as to whether this is the right decision?
Thanks!!

[Kaliska]

I'm not a bit expert by any means, but my first step from there would be a pelham. After all, any bit can be mild/harsh dependant on whose hands it is in. Why not go for a rubber pelham if you want something a bit softer?