RELcap PPMF vs Mundorf which one you prefer?

i mean RELcap ppmf vs Mundorf silver/gold.

Not exactly what you're asking, but Mundorf silver/gold were a great improvement over REL RT coupling caps in the phono section of my pre.

A lot of it depends on the equipment circuitry. One cap might sound better in one design than another. Do a search both here and the other forum Audio Asylum( go to the Tweaker's Asylum for more threads on caps), searching both these caps as well as the components you plan on trying them in. It might be best to try both in one component at a time, let them break in properly, and then decide which sounds best. Then move on to the next component and do the same thing. If you choose a particular cap and mod several components all together, and then decide you don't like the sound, you won't know if you're coming or going, if you know what I mean. Have fun and good luck, though.