The bottom bracket of the bike I'm working on (see my other thread) is toasted, so I've been to a couple of shops asking for parts: it seems hard to find an exact replacements, though. The spindle dimensions are, to the best of my measuring skills, 34/57/40 mm, so 131 mm total length.

One shop offered a 130 mm replacement with a shorter central section (the one called "B" on Sheldon Brown's site), probably a couple millimeters. They said it's not a problem. Also the current cranks (Ofmega) have nuts, while the replacement spindle is hollow. They said this is not a problem too, and that bolts are better.

The replacement has 9-ball bearings (same as the original equipment) which I read are not as good as 11-ball or cartridges. When asked, they replied there are no BBs with 11 balls (Sheldon Brown disagreed) and that cartridges only come with shorter spindles (I've found an online shop carrying a Sunrace BB with a 131 mm spindle).

Did they lie to me about the rest too?

Last but not least, all the specs of the Sunrace seem OK: spindle length, shell width and thread. Is there are any other reason why it wouldn't fit on my bike?