I bought an er32 r8 taper collet chuck from rdg in november. It was marked myford. On inspection it seemed ok apart from the nut was stiff on the body of the chuck. The first time i used it was holding an edge finder. Found the edge and swapped for an end mill, 4 or 5mm in diameter. Took the cut and went to change to a larger tool, the nut slackened off a quarter turn and siezed solid.
I took the whole thing out of the machine and sent it back to myford. After about a week i emailed them and they told me the reason it seized was i did not know how to use it, the collet had sprung in behind the nut, which couldn't be removed, and they were returning it to me at a cost of £13 !.
Despite the myford name, i reckon they are the usual Indian tat, the nut and the body of the chuck were similar in hardness, galled and seized.
I won't be buying anything with the myford name on, and no more from rdg.
Buy a vertex, or a good, european, american or japanese brand, or see if you can find one second hand on ebay or here.