HT2, been there, done it, had BB reemed and sleaved as a result. I'm interested to know what folk are using instead of what the great ShiTmano are insisting we use. Me, I went back to HT1/Octalink and haven't had a prob since.
Octalink and Square taper.
Isn't Octalink Shimano? I use Hope BB cups - and of course HTII cranks - wont go back to Shim Cups! And yes I know this is an internal BB post 😉 Have you thought of alternatives to HTII EXT BB Cups?
Middleburn and Shimano Square Taper (UN72)
Square taper on my SS and commuting bike
HT2 on everything else (including road/cx bikes).
Octalink is indeed Shimano. It's quick'n'easy to install and lasts ages so naturally it had to go.
Middleburn and SKF Isis BB on all 3 bikes.
Octalink on two bikes and SSC isis on another, which is still silky smooth after a winter of abuse - very impressed.
Square taper on the CX (Shimano XT) and the roadie SS (White Industries BB)
Race Face ISIS on both MTBs (still going strong although they have both broken several times in the past and been replaced/repaired under warranty)
Octalink on the road bike (old style Dura-Ace) and on the retro MTB (old style XTR)
They all work, not seen the need to change them so far. Really don't want to change the ISIS since both sets of cranks were bloody expensive! Plus one of the BB's is Ti.
SKF ISIS with a Bontrager Lite chainset.
octalink on mine, have raceface x-type on Kona but not used it yet so dunno how it will compare...
Square taper (UN54)