simon, i told you should sort that det by turnin down your boost or a remap, (good old rollin road mappin, that det's on the road)
and you need det can's to hear it, if you could hear it by ear then thats seriously detin.

haven't tried tesco stuff,

but sainsbury's super is good, had less det with that than optimax and bp, wen testin them on my hi comp xr2tt.

but i think ding aling might have a point for one , wot fuels last the longest b4 it goes off?