In regards to hand/feel, a horsehide jacket will usually be stiffer than a lambskin one. I bought into the horsehide “hype wagon” years ago, and every vintage HH jacket is still relatively firm.
Yeah, I mean I kinda knew what I was getting into, but everyone says oh it breaks in with time, but broken in still means the jacket can still stand on its own, so the tinman feeling while wearing it doesn't really go away. At least with raw denim it does break down and get soft over a lengthy period of time. But just like HH vs lamb, or raw denim vs washed denim with some stretch, it will never be as comfortable.