The game has never crashed on me and the loading times are 10-15 secs for big hubs and 5 for interiors. True, the loading times are long enough that I've started to think of routing/doing everything I can in an outdoor area before I transition to a new place, but that's it.
And this is the best RPG to come out since long before Oblivion (which was great and all but sucked as an RPG).