Buyer representation could represent a more difficult challenge if you don't know the product. Agents overcome this by previewing homes BEFORE they show buyers property. It wasn't an issue for me on the buy side either in St Louis.
If you are an agent that does a lot of business directly from your office, I believe it might be a hinderance especially if competing agents have offices near your farm or target area. I have asked myself this same question and have decided it is best for both my clients and me to have my office near by.
Hope this helps!
When prospective clients peruse the internet for lisitngs, they will call the agent they see regardless of where the agen't office is. So in sum, if you are away from your farm, make sure your internt presence is strong in your farm.
I'm someone who likes being in the office - I like the energy, the focus, the bits and pieces about the business you pick up each day. If I lived too far away it would be too easy to not go in. And I'll confess I'm a big fan of gotomypc.com - and that makes it all to easy to not leave the house!