I do have a bunch of Lee moulds in all sorts of sizes and configurations/calibers.
Many are RB moulds and many are bullet moulds. They form maybe 30% of my 83 sets of moulds/mould blocks.
They work fine if hot and kept that way, same as any other mould. If you cast too slowly, THEN you may have block filling-out-properly problems.
I wear heavy padded leather work gloves when casting now and open the spruce cutter with my hand. Gor sticking balls or julkets, I tap the hinge with a hammer handle-wofks perfectly. Been using the same small hammer handle for 45 years.