Back in the late 80s, my brother and I played SOM so much our mother threw the game away.
I was an early OOTP adopter, and I have to say that for the last 8-9 editions of OOTP, OOTP blows away SOM on almost every dimension. Want to replay a single season? OOTP can do that. Want to run a crazy fictional league on Mars? OOTP can do that. Want to start an MLB league now and then let it develop organically with realistic financials? OOTP can do that.
Some say SOM is "more accurate" for single-season replays, but from the perspective of a statistician, it is a somewhat misleading form of accuracy. SOM will give a pitcher a low BABIP in a year if that's what the pitcher actually received that year. But we know that pitchers, with few exceptions, don't control BABIP. So SOM will replay a season pretty closely with the "right" proportions of popouts, hits allowed, etc., but won't actually let a season replay as it "could have" played out had pitchers not been unlucky with their fielding, say. In terms of big-picture realism, OOTP actually has SOM beat, because OOTP accords better with
baseball theory (how we know the game actually works). I still have a sentimental attachment to SOM and maybe I'll pick up the card game at some point to play with my daughter, but the only game I would play for myself is OOTP.