Hubs wear, bearings are made to a tolerance.

Depending on the vendor, some of them label dog-plop aftermarket bearings with a genuine number.  I trialled some a few years ago for one of the 'Names' and they lasted 60 miles and the hopeful supplier was told "No thanks".  Another Name was selling them under the proper number.

Most are too tight these days when fitted and bind up, so I shim them with balljoint spacers until they're good.

It's almost like proper engineering...

I think the last time I got the separate-spacer bearings they were 07087 cones with 07210X cups, but the supplier had remarked the boxes with the GHB numbers.

I just tried those number here and sport , did not come up with anything. Even googled, nada.

I did measure the depth of both bearings and they don't match. I just tried to leave the aftermarket races in the hub but the hub slid back and forth about an 1/8 of an inch. The after market races had to go as well. I put the oem timkins races and repacked the oem bearings back in the hub. Before I did, I took a loop and looked the bearing surfaces,  no pock marks, very clean.

that is a difficult thing to do by measurement, unless you have a reference set to compare.  I never liked these built-in-spacer bearings,  I liked the GHB087 with the 2A7355 separate distance piece.

Thanks for the reply. Way back when, I would tighten the nut, grabbed the tire and tried to wiggle it. The after market ones must be way off. I will measure both inner races tomorrow and post the results.

I have seen same complaint on UK Mini forums, people having to shim the inner race to get clearance when the nut is tightened.  Bearings are often non-refundable items, you might not be able to send them back.

Has anyone used the after market rear hub bearing GHK1548?

I noticed my tire wearing faster on one side. I decided to pull the hub bearings and noticed that they were dry, no grease at all. The bearing surfaces are all clean, no burn marks or pitting. But I decided to replace any way. Hammered the old races out and hammered the new in. Packed new bearings with grease and torqued. At 45lbs I could hardly turn the hub. 

Has anyone had issues with after market GHK1548? 

I'm thinking that I may repack the old Timkins and reinstall them.