Another vote for SFO, as long as the price difference is acceptable. OAK is much farther from downtown SF by car, especially if there is any traffic on the bridge or the 880 (and there almost always is). Bart to SFO drops you directly in the international terminal. Bart to OAK drops you in a bad East Oakland neighborhood where you transfer to an unreliable bus operated by surly Port of Oakland employees. SFO is much more crowded than I've seen it in a few years, but it is nothing compared to the clusterf*** in the terminals at OAK.