What I did was get longer housings and exit the cables near the stem along with the brake cables. It works well (don't have a lot of miles on the bar ends yet) and IMHO looks way better.

For what it's worth on the secondary discussion..... I went bar ends because a) I was curious as a lot of people like them and b) I was too cheap to go ultegra 9 STI

I have found shifting no problem (but then I didn't really have a problem with down tube) and have had no issues with excessive steering input.

The only issue i had was that I have found I have to be careful when stopped at a light so that I don't bump the shifters and then set myself up for an unplanned shift when I start up again