For those who feel the castors go in extremely hard, you are correct. I 'm a big guy as like 6'2" and 220lbs, it was all I could do to get the first couple in. I then put on a thick oven mitt to pad my hand and moistened the castor shafts with a bit of saliva, (do not lick these to do this step). No doubt a light spritz of WD 40  or even chapstick/vaseline rubbed on the shaft for those who have no WD 40. Any of the latter would do the job better without the possible issue of rust due to saliva but I was too lazy to walk to the garage. They slid in way easier with this method.  Hope this helps anyone still having issues and for those who wish to purchase. I would def buy again.

Pros: Solid chair as advertised, actually better than expected.
Cons: UPS delivered in rain, box was trashed when I got home. By design the chair will most likely not slide under your desk, in time arms will be beat if you have kids(or sig others) that dont use care when pushing chair in.