Looks matter to me. However...
- would I buy something that looks good and sounds good? Of course. This is the ideal.
- would I buy something that looks bad but sound good? Yes. Sound matters more.
- would I buy something that looks good and sounds bad? Of course not. Again, sound matters more. No one buys an amp to stare at it but never turn it on (unless you own a stereo museum or something).
If choosing between various components, I would choose the one that looks best if it was a tie in terms of sound. But at the end of the day, what you want more than anything is to sit down and listen and to really connect with the music. It's all too easy to assemble a system where this doesn't happen.