Really no 1 reason.
Having other revenue sources for the company/man during hard times is part of it, GREAT customer service is part of it. I think the biggest part of it is knowing his Niche.
Mid level price with consistent performance and quality. He didn't race to the bottom and let quality suffer and he didn't try to be the latest and greatest high end gun that dies off as soon as money is tight.
Mike knows that there are things that could change about the Phantom to make parts of it better. Those things don't see the light of day if they mean making performance less consistent, raising the price or settling for low quality.
Thats why we can argue about springs until we are blue in the face. He puts springs that work no matter the conditions in there and if you want to fine tune to improve something you have options.
Thats why you don't get fancy milling that raises the price beyond it's mid level range.
Mike offers 1 feed tube. Is it the most efficient it possibly can be? The math I have seen says no... But I've never broke one... and by focusing on that 1 quality control is high. I've heard of someone showing a CCI TP and one from another (High end) company to a engineer that makes parts for jets. Word is he said the other company's piece never would have made it out of the shop because of poor quality.