P100 filters should remove 99.97% of the fine dust, metal and wood particles but spray painting/fumes I think you need different types of filters (charcoal?) depending on the type of paint you use, plus probably would be advisable to use pre-filters as well.
I don't think that you can get a one type mask with a "does all" filter. I don't have a air fed welding mask, I just use a 3M 7502 with a P100 2091/2097 pancake filter for general welding and woodwork, and another 3M 7502 mask with a different spray painting filter and pre-filter on it for painting.
So the Speedglas with air feed or something similar will be fine for the welding part ( that is what they are designed for) but I don't think that I would use it for spray painting.
I don't think that you can get a one type mask with a "does all" filter. I don't have a air fed welding mask, I just use a 3M 7502 with a P100 2091/2097 pancake filter for general welding and woodwork, and another 3M 7502 mask with a different spray painting filter and pre-filter on it for painting.
So the Speedglas with air feed or something similar will be fine for the welding part ( that is what they are designed for) but I don't think that I would use it for spray painting.