I cant speak to experience with their customs, but I have enjoyed dealing with them in the past...I had Cole's do some work for me, a crack repair in a uggie forend and a refinish and chase the checkering on my Caprinus. They did a great job, excellent customer service and quick turnaround time.
Another time, I was considering buying a project gun, a used pre war sauer, that had some issues. They took the time to evaluate the gun for free when I walked in and saved me a lot of money and trouble!
Good luck with your project
