Straight shooters. My situation was unusual in that I wanted to replace an existing system while using components. And then when the utility capped the size of my proposed system, I fought back by filing a complaint.
This added more than a half a year to the project, but Ipsun stuck with me.
I researched my situation enough that at times I had something to teach Ipsun. But they always listened, never talking down to me. And when it came time to install they delivered as promised, on time.