I am looking into cutting my own frames. I have already ordered the Clearmount system but was going to buy a saw local. I was curious if you were to buy a miter saw would you suggest a 10 inch or a 12 inch?
Better check with Clearmount and see what they recommend. It may be that some brands are a better match. Also, while a 12-inch saw let's you cut wider mouldings, the Clearmount you bought may only work with a 10-inch saw.
A 12" blade will give you a little more capacity, but at a cost. A 10" blade will cope easily with 99% of anything you will realistically need to cut. There is the odd profile where the blade will not quite go all the way though. But that's on 4"+ wide mouldings of which there aren't many. In cases like this it's easy enough to finish the cut with a handsaw.
Like David mentions here plus do the math. How many wide frames will you need to cut. If the number is small it will take a lot of time to break even on the price difference in saw and blades plus sharpening. If you only need to order one frame per month as a chop because of width then the smaller saw would be the way to go. If you needed to upgrade a couple years down the road there is a good chance you would be buying more of a commercial set up than a single miter saw so you would be able to sell this one and put the money toward a large saw.