Someone, somewhere in the forum mentioned that if you can blow a match out while wearing the mask it isn't doing anything. I tried it with two different bandanas - one was OK, the other wasn't. I could not blow out the match while wearing any of my two-ply fabric masks.
They will probably be a little more than pre-ordering them and they will probably have different designs available. Will have to wait and see what the prices might be but I don't expect them to be outrageously priced.