Originally Posted by Morelock

Some of it is build quality. Some of it is that they are approved "NJS" (which people often equate to durability, although that's not particularly true)

Maybe the biggest difference is that the 7600 are "tuneable" for track (I've done it for some people, getting rid of the seals, using very low friction grease, "better" ball bearings, adjusting the "tightness") which is much harder to do on a sealed cartridge bearing. It's also not something I'd recommend doing unless you were doing it for one big race where every fraction of a second mattered.

Both are going to be fine. (If they are used 7600 hubs however previous user wear is something to be aware of... worn cups/cones/bearings can be expensive to fix) Modern times for most people, sealed cartridge is just easier to live with.

Originally Posted by topflightpro

Nothing. Go with Formula. My 7600 hubs have been a PIA. Should never have bought them used.

Originally Posted by carleton

Yeah, my DA 7600 hubs were nice when new. But, they require maintenance and tuning after a couple of years. When they get a lot of miles on them or the grip nuts get mashed-down, the tolerances get wonky and you'll have a number of issues.

For worry-free use, use sealed hubs, as topflightpro suggests.