Used high oct since I've owned it unless unavailable. 
KRL said
oils, not fuel - you muppet!

As I've repeatedly stated - yankie spec 502.00 oils are shyte - and it is these 'yankie' originated attitudes and issues which are the cause of many alleged problems on VAG engines . . . . worn HPFP cam followers, 1.8 20vT sludge, worn PD camshafts - all yankie probs by adamantly refusing to use the correct VW oil specs.
Joe, I presume you've always used Castrol Edge? If so, this vindicates my claim that Castrol is considerably better than even 504.00 yankie brews (<cough>Mobil 1<cough>).