I have a problem lumping Octalink and ISIS together in terms of durablilty. The early ISIS bb's were indeed pitiful, leaving a lot of customers frustrated and angry about their ISIS cranksets. Octalink never had those problems, the stuff is rock solid and has been since the day Shimano put it on the market. I recall seeing BF member Hillrider report here saying he's got 19,000 miles on an Octalink road bb. I've had similar results with Octalink mtb bb's, as have several of my riding partners. The ISIS manufacturers eventually got their act together, at least to the point that better reports of their durability came along. I've got a Nashbar ISIS crank/bb I put on an old touring bike four or five years ago that now has over 10,000 miles on it with absolutely no problems. The bottom bracket cost me $22.95 from Nashbar.

The reality is that this stuff is a fading standard what with the newer "standards" coming out, and in most ways Octalink has nothing on square taper cartridge bb's, but in my opinion Octalink in particular gets a bad rap sometimes. Especially when it's lumped in with ISIS in regard to durability.

To the OP, I still say stop fretting over all this and go ride your bike. You're overthinking it.