Octalink is a nightmare, there are various spindle lengths but there are also 2 versions of the spline, after the first lot started breaking they increased the length of the interface so earlier cranks end up with a narrow chainline on later spindles, IIRC
but the road cranks all use version 1 with the short splines, and there are only two lengths, double 109mm and triple 118mm. There are no 73mm BB versions of road BBs, so you don't have the option of shimming a 73mm BB in a 68mm shell. I'd avoid like the plague as it's defunct proprietary system, so your chances of getting replacement BBs in the long term tends toward zero.
Octalink is a nightmare, there are various spindle lengths but there are also 2 versions of the spline, after the first lot started breaking they increased the length of the interface so earlier cranks end up with a narrow chainline on later spindles, IIRC
Chain Reaction have pretty much all the lengths of version 2 in Deore grade BB-ES51
http://www.chainreactioncycles.com/Models.aspx?ModelID=908
but the road cranks all use version 1 with the short splines, and there are only two lengths, double 109mm and triple 118mm. There are no 73mm BB versions of road BBs, so you don't have the option of shimming a 73mm BB in a 68mm shell. I'd avoid like the plague as it's defunct proprietary system, so your chances of getting replacement BBs in the long term tends toward zero.