M.M.
We've used one for years.
I like someone that is not tied to a particular company (like Northwestern), since they'll always leads with investments from their employer. I like an unbiased look into the market and offerings.
I would look for someone that doesn't try to sell you too hard on moving your money around. And depending on how aggressive you want to be with your investments, that person's tendencies should match your own. In other words, is your investment approach aggressive, or more conservative. And if it's either, do you want someone that matches that, or might advise you otherwise (slow down, speed up, etc...)
We meet with our guy 2x/year. We're both pretty conservative in our approach. He's given us good advice in how to maximize our portfolios, and helped us get on track so that college is paid for for the kids by the time they get there. He'll come with suggestions for new market offerings, but doesn't push us hard if we're not excited about the move.
So it's more of a question of how you like to manage your money now, and what you're looking for in someone to help you with it.