Decent quality pair, not too much play in the lead screw nut but the springs are very weak when used under preload to reduce play. I guess they're all weak no matter who you buy them from. You'll need to replace the 10.15mm ID x 55mmL and 16mmL @ full compression stainless steel nibs with something stronger as I can see these nibs don't work too well on a decent sized print without ghosting, especially when printing with many vector changes .
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