I have done business with both companies and have seen what comes with both kits. I suggest going with Willman-Bell. In my opinion, the pitch that comes with the WB kit is better quality (Newports was way way too soft and has to be heated a long time) and you get 2 blanks that can made into a mirror. The WB kit even comes with instructions, while the Newport kit does not. I think the WB kits cost a bit more, but it`s worth it.

If you plan to go with WB, include a mirror making book (they sell them too) as part of your purchase.