I was a Sales Engineer for a number of years in the electronic component industry. I'd say the experience working heavily with customers is invaluable. You can really make a name for yourself if you work hard and help to solve customer problems at key accounts. If you want to go into sales, marketing or management, I can't see how you can go wrong.
On the other hand, if you want to be in engineering management or research, there may be some snobbery there that the engineers on the sales side are not as smart. Which in my case, is probably true
