I find myself increasingly drawn to the early stuff, not least because I have such fondness for all the rock 'n' roll guys from the 50s (Chuck, Eddie, Larry, Carl, Jerry Lee etc. are pretty much all I play).
So, for me, it's the first three LPs, and even more so since seeing 'A Hard Day's Night' recently at the cinema and last year's 'Live At The BBC Volume 2' CDs.
However, it's more clear cut with regard to The Stones; overwhelmingly my favourites are 'The Rolling Stones', 'No. 2' and 'Out Of Our Heads'.