Favorite preserved steam locomotive? That's a toughie.
Running - Ventura County #2 at the OERM. There's something nicely approachable about its size, yet it still gets the visceral feeling and imagery of a steam locomotive.
Static - Southern Pacific 3025. I absolutely LOVE high-drivered steam locomtives, and I've always had a soft spot for that classy locomotion oddball that is the Atlantic wheel arrangement. I'm incredibly fortunate I live within a Metrolink ride of the sole preserved example of one to the west of the Rockies and that I have built up the 3-d modelling know-how to do it justice in MSTS.
Favorite museum is an easy one though--the
Orange Empire Railway Museum. I've served as a volunteer conductor there, visited a number of times, and taken the main in several streetcars and an ALCo.