Let's see...smooshy, soft leather? Muse leather is not smooshy-perhaps soft when you touch it, but the bag is stiff and does not bend easily. If a muse seems to bend and fold easily, then there is a good chance it is fake. Early versions of the muse in buffalo leather seem to be 'softer', but the calf leather used now takes a while to be broken in and even then, I don't think it becomes smooshy.
The medium black downtown is smooshy and soft in the deerskin leather (without the front pocket).
Which one would make a great first bag would depend on your needs and lifestyle. The muse is classy and the OS can be heavy. I encourage you to check out the reference thread to see pics of both bags.