Nothing wrong with asking advice. I am up between the Red and the White. I love my white L900, and am not tired of it. But, I really like the red the more I see it in pictures.
Yellow- just too bright. On the phone this big, it could cause accidents.
Black- too common. If you are going to stand out having a 100 acre phone, might as well be original and stand way out.
The smooth back of the red may just be too much on this large phone for me, so white it may be.
Besides, first thing my clutsie tush is doing is getting a case. A serious case. I have beaten 2 of my last 3 phones into submission by dropping them, so no chances are going to be taken on my next one. I will go naked with it in casual settings and protect it with a case as close to a tank as I can get during work hours.