The main concern with balloon-head cases, if you get them as fired brass, you don't know whether or not they may have been fired with mercuric primers. If they have, there is no way to effectively clean them to restore the brass to safe condition. Brass cases which have been fired with mercuric primers will be brittle and will frequently blow the head, even with standard pressure loads. My original 1906 Colt SA has a loading gate which is not numbered to the rest of the gun for that very reason.
Unless you are working with new factory-primed brass you know has non-corrosive, non-mercuric primers, or you pull down, decap and reprime old ammo which has never been reloaded, you don't know what you have. American commercial primers after WW1 were generally non-mercuric. Non-corrosive primers came into use in the late 1920s. If the fired primers are white tin-plated and of WRA, Western or Remington-UMC headstamp, you are probably OK.
If the primers are copper colored, or if white metal but headstamped U.S. Ctg. Co. in the old orange and blue boxes, I would not take a chance on them. Sell to a collector.