can i use the nut from a rcbs die on my lee dies i like the lock nut better

I would say sure.

ok i like the lee dies but i like the lock nut on rcbs

Most lock rings are interchangable, though not all. Check the play in the threads once you swap out.

On a similar theme, I had to replace lock rings of brand new RCBS 38/357 dies recently as the outside top to bottom thickness does not fit my 1980's vintage Bonanza press; dies slide in and are suspended above the ram, whereas most presses accept them threaded into the top of the press. Swapping out dies takes only a few seconds though and I thought that was a neat idea back then. Though the idea only works as long as the industry uses a non-changing standard for lock ring dimensions...and I'm finding out that many industries like to change standards over time (sigh).

Yes, they should work. I've done the same thing, though I really like the Hornady lock rings better.

I thnk it's gonna depend on your press. I have a turret press and the RCBS locknuts are too big. They hit the next one over. The threads are the same tho.