Dan,
I have some experience. About a dozen pens thus far. I printed Mike's instructions and have them posted next to my lathe. I never even tried another approach (with Pens Plus) because Mike's process, while time consuming, works very well for me.
I have tried this finish on antler. After talking to Mike, he hadn't tried it yet and neither of us were sure it would work very well, but on my 2 test pens, I like it and from what I'm observing the finish is holding up and the satin shine is still consistent and shows no signs of dulling.
I use the MM. I bought a fresh pack and dedicate those pads to only Walnut Oil application and keep in a ziploc bag.
My only thing with Mike's method that I've struggled with is the part applying the Pens Plus. I use the same spot on the application paper towel over and over as Mike suggests, but it really starts to deteriorate on me and come apart from saturation before I start getting that "equal shine" during both application and buffing that you look for to know you're done using his method. I'm convinced it's my technique and perhaps a combination of how much Pens Plus I'm using, lathe speed, and choice of paper towel that I'm struggling with and I'll figure it out eventually.
But to answer your original question, yes, I've tried this finish and I love it. It is the only finish I use on wood now and it is potentially becoming my favorite finish on antler based on initial results of a couple test pens.
I have also used Mike's methods and Pens Plus on larger items made with wood - like Pizza cutters, 4-in-1 screwdriver kits and even the stainless steel travel mug kit on a chunk of claro walnut (that is beautiful stuff by the way).
Mike's process is time consuming, but I think you'll like it and I think you'll find that it holds up pretty well compared to other finishes.
Kevin