I have made 2 DIY screens now; one a matte white, and one a silver fabric. The white one (Parkland Plastic) was easy, and had minimum negative side effects. The silver fabric causes multiple problems including hotspotting, limited viewing cone, and color shifting. It also has great up sides, such as better blacks, sharper picture, more dynamic colors, whiter whites. The silver metallic base is a much stronger beast, but it needs to be tamed. I think that the strength of the Vutec product is that they spent a loooong time perfecting a process to tone down the silver, without losing it's good properties. If you apply the wrong topcoat, you will just end up with a dull grey finish, which is a huge step backward. I just don't think that a quick and cheap process is going to be found that will provide the exact qualities necessary for a great overall picture from a silver base.
It is like viewing a show car with 15 coats of lacquer paint and asking, "How can I get my car to look like that?"