Hey Ben,
I have the 16k for here and the 25k primarily for deep jigging at home...I think they are fairly well made and the drag appears to work well...I disassembled mine and rebuilt using Cal's on the CF washers. The addition of Cal's will add some drag to the overall function at the lower settings but does make for a smoother mid/high range.
I personally brush the drag housing with Cal's - top and bottom just to provide some additional corrosion protection..the 25k is a big spool