Jan van Leyden
Adventurer
I prefer Race to San Juan, mostly because San Juan is... well, sort-of solved. I don't recall the card combo offhand, but it's basically focused on the one that gives you extra VP for plantations, and then building a crapload of plantations really quickly. Most of our games of it have ended that way for the last half-dozen plays or so, so I've pretty-much lost interest.
Beg to differ. This Guild Hall plus Plantations strategy is only so powerful if your opponents are helping you. This strategy needs a three-card-cycle (Overseer -> Trader -> Builder) for nearly each plantation you want to build. Guess how long this cycle takes when you're on your own with the growing/selling part.
And with this strategy you absolutely need the Guild Hall. What do you do when you have to wait for it? And what do you do when it is dealt at the start of the game? Do you really use a strategy which gives you few cards up to the middle of the game? Be prepared to have the Guild Hall still lounging in your hand when your (aggressive) opponent builds his 12th building.
To be more flexible, you need several purple buldings as well (Smithy, Poor House, Aquaeduct, Black Market,...), which in turn reduce the value of your Guild Hall.
The proposed strategy is a seldom winner in our games.