I have the red and the finish wears very quickly on the razor head. I would personally avoid red and blue. Black seems to wear well and matte silver is also nice looking.
I have the matte stainless so I am obviously prejudiced. I have to say that it looks as good after two months of mostly daily use as it did when I bought it. To me it is kind of like buying a new vehicle. The black looks really good when it is clean but it shows dirt/ road grime really quickly. The silver/gold/ champagne color looks cleaner longer. YMMV
Any added color may fall off over time, so I prefer to the original matte color.
Although bright colors such as red/blue are attractive, I also avoid using red on shaving items to ensure that I can be spotted in time when I am bleeding.