The best is Pecards Leather Dressing.
They make the same formulation as motorcycle leather dressing, antique leather dressing, and classic leather dressing, just labled differently for different markets.
The leather dressing is like a paste, and needs to be rubbed in with the fingers, and then needs to be allowed to penetrate the leather for about 6 hours. Then buff it briskly with a clean cotton cloth, and that will buff the residual waxes on the surface, and it will come out looking awesome, and very well protected.
They also make a cream, but that isn't really for heavy duty items, and more for gloves and stuff.
The leather dressing is what's best for leather jackets, leather pants, and boots.
New leather should not need any dressing for at least a year of wear.
Then, maybe once a year after that, if it looks like it is getting dry or scuffed.
I've also used mink oil, and that works too.
But, I think Pecards is better.