I'm actually not using my PLU ML-78 with blue switches anymore. I like the MX browns on my Filco better.
Build quality is fine. It's pretty heavy, feels solid with no flex. I also have a Filco 104 (browns) and a Steelseries 7G (blacks) and all are build equally well. Caps are not better or worse than those on the Filco. The cable on the PLU is a little bit thicker but the spacebar, shifts, enter and backspace on the PLU rattles more and don't sound as nice. I will try to get some grease and see if that helps. The PLU is a nice board and I like the white version.