Based on what I've read and seen, I'm a fan of their quality, company/history, and customer service. I just wish they brought a wee bit more bass and airiness to the table, ala a David Harvey Gibson. I was even considering doing a search for, or starting a thread on, ways to add more bass and airiness to a Collings MF such as moving up to a Medium Plus Monel set, finding one with an Engelmann top, or playing the heck out of it to "open up" the red spruce top.
However, this MF played by Nate Lee sounds fantastic. It's one of my favorite YouTube mando videos.
https://m.youtube.com/watch?v=3K1qmT_BhfI