3M - 7500 Series Reusable Half Facepiece, Model 7503 (Rating: 5)

http://www.amazon.com/gp/product/B000Z53WKU/ref=oh_details_o01_s00_i02

After trying a few masks, this one is definitely the best so far. I rarely give 5 stars, and in fact this is my first 5 star item that I have used. Its comfortable, inexpensive, and has a down firing exhaust that prevents any condensation on safety glasses. The adjustments for the straps are easy and it has the best detachment mechanism so you aren't wearing out the adjustments.

Cost: ~$20

I am using the following particulate filter.

http://www.amazon.com/gp/product/B00328IAO0/ref=oh_details_o01_s00_i01

I am also using the following organic vapor cartridge when doing finish work.

http://www.amazon.com/gp/product/B000XBKLLE/ref=oh_details_o01_s00_i00

The woodwhisperer was right, this is a very nice mask.