Canon - Excellent image quality, medium build, lots of features (like bleed, yadda yadda) if you need to output proofs and stuff recommended.
Kyocera - Cheaper end of the market, the new models are supposed to be really good, especially compared to the previous colour ones, reasonable service costs etc. Same machines are often rebranded as UTAX and Copystar in diffferent markets.
Just noticed you said Konica, don't know about them much.
Sharp - don't know
Panasonic - Supposed to be awesome , built like tanks, easy to fix/repair/maintain, pricy, parts are expensive, loaded with features as well, but Canon probably still better feature wise.
Personally I'd go for Panasonic, had a few canons and never been that impressed. How are Xerox these days - I think they kinda suck in the last few years?
Obviously the contract you get with the thing will matter a lot, your volumes, and the type of thing you print.
There IS a good copier forum somewhere (US based) but dammned if I can find it..
edit Knew it - soon as I posted I found it :
http://www.copytechnet.com/forums/