i've used both over the last 45 years or more. mostly lyman for CF stuff and Lee for roundball ... i've had excelllent result with both, but you
absolutely must R.T.F.I. (that's Read The F*(%ing Instructions) ... for those of us who might have concerns about the potential loss of machismo (as in, ten points off your Man Card if you're caught reading the instruction book) i would advise taking a long neck out to your pick up and reading the pamphlet in privacy ... wrap a girlie magazine around the front so nobody will know ...
don't beat on them to get the ball out. a light tap should be all it takes. some people have their favourite magic stick, but i use a bit of firewood that i stole from the pile. when it gets too chewed up, i use it in the woodstove and get another piece... you're not whacking it with all your might - it should last a good long time.
cast outside, and you want to by upwind of the pot so the fumes and funk blow away from you ... (i flux with beeswax - works great but smoky)
wear leather gloves, long sleeve shirt, closed toed shoes and long pants: you do NOT want lead splashing on bare skin
I use the prescription glasses that my job provides, but if you don't have to wear corrective lenses, get some goggles
also (and don't ask me how i know), wear a hat or a bandana so that, if you sweat, none of the moisture can drop into the molten lead. if it does, the droplet will instantaneously flash to steam and splatter molten lead all about. this is very dramatic and very unpleasant.
of course, don't eat or drink anything while you're running ball (if you do it right, your hands will be too busy anyway), and wash your hands after you're done.
the alarmist hysteria about lead poisoning is pretty much that: alarmist hysteria. unless you're giving you three year old a roundball to chew on, you're OK. after all, they're for shooting, not eating.
enjoy your making of roundball, and then Make Good Smoke