I see a lot of stuff online about guys using different brands combined to refinish their project. Ex: primers by PPG, basecoat by Metalux and the clear by Glasurit. I was always under the idea that you should use a complete system. But now, I have to deal with this issue. Im in a situation where I have Metalux bascoat in Wimbleton White and Montana Big Sky Primer Surfacer. The shop I bought that from said its made by the same company and is compatible. Unfortunately, they did not have etching primer and said its on order. Last time somethng was " on order" in this place it took a lifetime to get in. I got a job to get done and would like to know what chances do I take using an etching primer and clearcoat made by other companies with the stuff I already have?