Does anyone have experience with Manufacturer Rep companies?

I'm exploring an acquisition of a Manufacturer Rep company for a commercial industry that I'm familiar with. They have territory exclusivity, a long history of success, a complimentary consulting service, low customer concentration, and operate in a niche segment with few competitors. Their supplier relationships are long-standing, and while the revenue is project-based many of their clients have been with them for decades.

What are additional questions I should ask? Watch outs?