Mogami is high quality wire. Many love it and those that do seem to stick with it and forget about wires. Others try it and move on to other brands, usually saying its a bit dull or lifeless in their systems. I like it a lot for pro audio and for connecting instruments to amps but havent tried it in my stereo system yet.
Cardas is generally much more expensive and has many fans.
I would like to compare the budget cardas 101 to Mogami but havent yet. the higher end cardas is in another league.