My favorite is my first saddle, which I still have. It is a Crosby sovereign prix des nations the classic model with no knee pads. When I bought my first horse my trainer had some tack that a friend who had fallen on bad times had given her to sell. Amongst the items was this saddle and it fit my horse beautifully. It was brand new never been ridden in, but had a cut in the seat where a vengeful boyfriend had cut into the saddle leather with a knife. I got it for $300 and sent it to a saddler who used to work for Crosby to have it repaired. She put a patch on it, that makes it look like it was made to be there.
My least favorite is anything with big knee rolls and a lot of bulk. I am also not a fan of synthetics. I too am a fan of classic look of leather and love to soap up a leather saddle and make it shine.