I have about half and half RCBS and Lee dies, some calibers both brands. some calibers I use the brands mixed on my turret press, some calibers I use RCBS for sizing, Lee for flaring, etc. I have seen no difference in the quality of the ammunition that is produced. some of my RCBS dies have been bought second hand, some new. When I find a need for a die I get what I can find at the best price.
As for the locking rings, hated them at first, changed all of them out for other locking rings. But after using them on two calibers and learning to use them properly(watching the Lee videos on you tube) I am a believer in them and have gone back to them on all the dies I use on the turret press. I just do not have enough left over rings to use them on all my dies.
And yes, you do have to have wrenches hand at the bench to retighten the decapping pins, but have not had to in a long time.
David