The Lee Factory crimp dies are excellent for all rifle cartridges and for levergun use are superior to having a crimp groove cut in the mold. However, I definitely don't recommend them for revolver ammo if bullets are larger than nominal for the caliber, i.e. larger than jacketed bullets.
If ordering any revolver bullet mold from I put a crimp groove wherever the customer asks for it, or to fit the gun of interest if the gun name is given. All other mold makers put crimp grooves in their revolver bullets, but the customer doesn't get a choice where they are. I also cut crimp grooves in rifle bullets on customer request if a swaged throat slug is sent with the order, but recommend against it if a Lee Factory crimp die is available for the cartridge. This because throats tend to wear quite rapidly and it is best to be able to seat at whatever length gives best accuracy and feeding.