If you had to choose...

^^:P i'm blonde and i wouldn't wear a yellow bag -- i think it's a great color for chocolate brunettes. though nicole richie has been seen with a yellow bal (albeit fake) in her blonde days and she looked great.

i love outremer, but i thought it was very bright when i saw it IRL and would worry about being able to wear it often. it's gorgeous though - so if it's about which one is the prettiest i'd go with that :jammin: if you're worried it'll be hard to match - go with sahara. i have a white bal and it's not as pain staking to keep clean as people assume.
 
I pick Sahara because it IS the most beautiful neutral color ever!!! And Outremer because imo, it's such a rare color- the perfect royal blue!!! And as far as leather, I think all 3 have wonderful leather. Good luck deciding!
 
I'd vote Outremer first. Then Moutarde...but since you are blonde I'd go with Outremer. Yes, its a brilliant bright shade of royal blue, but it goes with EVERYTHING! I have worn mine consistantly for the past 2 weeks and I have never felt like it clashed or overwhelmed anything I wore (and I am a jeans/cute top kinda girl)......:yes:
 
I think sahara is a true neutral and would work within a wardrobe best - yes is a lighter color - but I have not had issues with my sandstone - which is similar. Next would be outremer - gorgeous bright deep color - but would not match well with everything. Moutard - don't like this one... not a flattering color.