I really like RCBS molds - I have four of them and they are all winners. And they have some really outstanding designs and great product support. But compared to the number of Lyman, Lee, and SAECO molds that I own this is a relatively small number. Why? Because they only come in two-cavity versions, and I hate to use anything less than a four-cavity mold for casting handgun caliber boolits.
I can live with two-holers for rifles, since I shoot a lot less of them at a time, but pistol boolits are another matter.
Just to get a sense of what you guys think, would you buy an RCBS four cavity mold if it was available, say at a price competitive with Lyman's?