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To be honest i ptobably wouldn't mind doing it on anual or semi anual basis but my last big daytrip was August 2019, just after changing bb. Since than my daughter was born and the bike was mainly doing commutes and shopping trips.. max 20km daily. Now my experience with external bb's is very limited and I might have a bias, but i've never had any ptoblems with squate tapered ones. Never bent one, never got one stuck on me. I think last time i had to change it was after 5 years on daily beater.
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I've used Prestine with no issues in the past.
If you're doing a fair bit of everything, annual BB replacement isn't that much of a chore or expense. HT2 might last a little longer, or maybe not. I wouldn't go back to square taper.