Ya, they don't make one for the 887, so I milled out the model for the 870. The gap is aesthetically annoying but I've got big hands so the reach isn't a problem. They said they are working on a stock for my model, so until then this will do.
Not sure if I'd go with their percentages, but it is definitely a comfortable shoot, I don't regret the money or work I put into it, if that helps. Don't know if your application is LE or HD but either way I feel it has it's advantages. I don't have anything negative to say about it other than they don't make one for MY shotgun!