Staci,
My organization (Mount St. Helens Institute, ~300 volunteers in our system) currently uses Better Impact. While there are a few minor annoyances, on the whole I've been very happy with it. We used to use Volgistics, and made the switch about 2 years ago. That was before my time, but I'm told it was missing some important functions we needed. It was a long process to get all of our volunteers up to speed on the new system, but now that they're used to it, it's great. Volunteers especially have appreciated the mobile app (My Impact) that came out for smartphones last spring.
Better Impact does not integrate with our donor management system, and that's been a frustration for our staff, so there's been talk recently of switching to a different system that would do that. It's a LOT of work to switch and retrain everyone, and I'm hesitant that anything that tries to "do it all" often ends up not actually doing the specific things very well... Raiser's Edge has been brought up as an option. I'm curious to hear your thoughts on that.