In most cases, I'd automatically choose the vintage watch. But the SMP is one of my favs and probably, if not The Watch, one of the watches which marked the beginning of my WIS days. I'd find a way to have both, but if forced to choose would go with the SM300.
As for Watchco Seamasters: get them pressure tested before taking them in the water! My Watchco Ploprof leaked during an ocean swim about two months after I got it. All the parts were there, it just wasn't properly put together and I made a poor assumption. A WIS mate sent his Watchco SM300 in to STS and they remarked made a remark to the effect that they didn't think much of Watchco's watchmaking abilities. I think they've improved their technique, but they aren't an Omega SC.
