I now have a set of PFX and have previously owned Zulu 2's/A20. The zulu/A20 differences are basically personal preference, the PFX is a whole new level and should be for the price.
I love how good the quality of the transmissions are with them and overall comfort but they are a bit buggy, take 4 batteries, go flat quickly and make strange noises if the seal around the ear is disrupted (mostly when eating). What they do well they do well enough for me to put up with the other stuff but is annoying.