Mark - you are not quite right; San Lorenzo is on the Algarve in Portugal - a nice golf course though.
Lloyd - I have played Valderrama twice but I was not very architecurally minded at the time. What will strike you is the awesome conditioning of the course - you could have a good temporary green just about anywhere on the 18 fairways! The cork trees lend it character, and the combination of their intrusion into the fairways, and the fact that these can be pretty firm mean that the course plays much narrower than it seems.
San Roque Old is a nice course - quite hilly in parts, like Valderrama. Seve's brother is the pro there - you should book a 30 min lesson just so you can experience first-hand what a gruff, take no prisoners, largely charmless, guy he is!
I was pretty underwhelmed by Sotogrande Old. I don't think it is anywhere near the class of the others. I will be interested to hear your thoughts.