If you're thinking of using the modern best practices approach then epoxy and urethanes are the paints you're looking at using.
if you're heading in that direction then consider the top lines say don't use soda as prep for their paint system.
Some say NEVER... but, if you do then use someone elses brand.
If you can't find blasting material that's safe to use, you're not trying very hard, are lazy, or don't really G.A.S. about your health.
As Tim mentioned...if you think there is any safe way to blast panels, etc. with out wearing protective gear (the exception being an exhaust equipped blast cab) then you might already be overexposed to the lead in those old paints... poor decision making is a sign.
As to warpage I think MP&C
covered it here. 
