Best Graphics Print Quality - Colour Laser Multifunction?

I currently have an OKI MC361dn which seems to print terrible graphics (very 'muddy' missing detail) and I am looking for a replacement. Recently I have started printing some oil-proof labels for some bottles and the print quality shows up pretty poor and small text is difficult to read.

My wish list is:
- auto duplex scanning
- colour laser (inkjet won't do the labels)
- max $500-$600
- Best print quality for graphics

I have a short list:
Kyocera ECOSYS M5521cdn / M5526cdn
Lexmark CX410de
Brother MFC-9340CDW (or equivalent model eg MFC-L3770CDW)
HP LaserJet Pro M477fnw or even M377dw

But I really want to know anyone who has compared the output of these machines and any to avoid? I like the Kyocera as it has native 1200 x 1200 dpi but not sure if this makes a difference in real life.

I do very few prints overall so cost per page is not a major concern.