My experience is a little different that that of mboy’s above; I’ve had a set of the md7 hubs for the last three years and they have been very good.
In that time they covered all my general riding, went to the Alps three times, few races incl the enduro 2 twice, some uplift days etc. I’m 13 st and ride a solo so not exactly easy on them. I did end up cracking the front hub recently but went and got another as I’ve been that impressed.
The tollerances are tight so the bearings last. The free hubs are good, and you can swap the bearings easy on those. Very simple design and easy to work on.
They are very light as mboy said.
I’d reccomend them.