Then there is this post from another site:

"Called RCBS again yesterday, and sent them an e-mail regarding the stuck .223. Explained that out of the thousands of rifle rounds I've loaded, the ONLY stuck cases I've had have been as of very recent--when I decided to give Imperial a try."

Here is the response from RCBS--

Hi Jeff:
Return the die to us and we will remove the stuck case and replace any
damaged components. You want to avoid lube that is wax based or has any
wax products in the ingredients. 95% of the stuck cases we get back
here are due to wax based lube.

What happens is that the wax builds up inside the die and is like rubber
cement in there and the cases will get stuck every time. Your die is
under warranty and there is no problem sending it back to us. Have a
great day!

I think the biggest problem with any lube is using too much, and not keeping the dies clean. The Lee dies I have will sometimes "plug off" the vent hole with lube. I use the lanolin/alcohol diy stuff. Just my .02