Beltz - I work in the safety industry. There are tons of approved respirators available both online and in stores. Home Depot, Lowes, Northern, Ace, etc all have them plus paint stores can be another good source like Sherwin Williams, for example. It sounds like you don't like the more basic disposable type, so you may prefer a reusable rubber-type faceseal. They are available in many styles and materials at various price points. The nicest ones tend to be made from silicone rubber but they are pricier. Silicone is a feature, so if it doesn't say silicone, it most likely is not as the manufacturer would want to tout this. Any NIOSH approved filter would do the job for general dust like you are describing, but especially at a retail level you will typically find N95 and P100 filters most commonly (95% efficient and ~100% efficient, respectively).
I believe the Miller one noted above is made from TPR (thermoplastic rubber) which is not as comfortable or durable as silicone but a lot cheaper. I'm not 100% sure but it says "silicone free" so it sure ain't silicone... The problem I have with the Dust Bee Gone and similar masks is that they are unapproved. You have no idea what is does as it meets no real standard like an approved mask does. If it is approved, you know it meets basic standards such as fit, filtration efficiency and that the supporting quality systems to ensure the standards are maintained are in place and monitored. The Dust bee gone seems to have a very loose fit which is probably why people find it so easy breathing - a lot of air will end up leaking around the perimeter and not going through the filter. That creates a false sense of security/protection.
My $0.02...
-Dave
