It is hard purchasing something you know nothing about. You either get lucky or you ask around.
Mouse,
Given your time period and DCC-ness, the MDC engine is your best bet. Steam is still in the minority in terms of models sold, and DCC-ready engines for the 1880s are virtually unheard of. Your only other option for a better engine would be to buy a used brass engine, remotor it, regear it, and rewire it for decent DCC operations: not a very simple or speedy task!
I’d go ahead, Spacemouse–as I told you in the earlier post, the MDC locomotive is a good runner, and they’re STURDY! Are you getting the V&T, or is there one lettered for Southern Pacific? Either way, you’re getting a good locomotive, and it’ll look good heading either freight or passenger. Now start looking for those MDC 19th century passenger cars–they’re really handsome!
Best
Tom