I can't say for sure if they are on par with Mefferts, but I ordered the black one from DX, and I still think it is the very same one sold on Mefferts.
The center caps were glued on, but I was able to pry them off. I did not try that until after I saw the same one on the Mefferts site, and they were selling it with the center caps separate. I adjusted the screws, and now
it turns smooth. I plan on getting the white one and adjusting it as well.
Size and weight are just like Rubiks, which works better for me than Eastsheen because I have big hands.