I am fitting Mini R53 front brake calipers to a MGTF to upgrade the brakes. Having looked at a good number of used ones on Ebay they all look badly rusted but there are new aftermarket ones at very low prices. I presume that they are made in China but are they okay or just poor quality? The rebuild kits (new pistons, seals and guide pins) plus a pair of reasonable looking calipers are more than a pair of new ones, any comments?