I run a few active guitars, and only one is the X preamp. I swapped the standard EMG pickups to the X series in one of my E-II seven string guitars. I personally feel that the added headroom really helped keep a better signal for the 7th string. My other E-II seven string has the 57/66 set which has a different preamp to the standard EMG (don't know how it compares to the X series), which had a very similar feel to the X set.
I am a huge EMG fan, though I have a couple guitars with Blackouts (SSS & HSS setups), and one with the a set of Fishman Moderns. I really like the Blackout singles due to their ability to match the output of an active humbucker. That was always my biggest gripe with a HSS setup; having to compromise on either the humbucker or single coils. That is not the case with the Blackout setup. Now, I am not convinced of the greatness of the Fishman pickup (granted I am not a touring professional). They sound good, but not better to my ears when comparing EMGs. I have played a few different sets of the Fishmans, and I always feel like I am left wanting. I can say that they do track faster, and the sustain is crazy good, all the while being dead quiet. For me, the multiple voice feature is more novelty than function. I say that because though I have choices, I don't feel like the different voices really give me anything better than what I can achieve with an EMG that has its one sound (and to me that one sound is much better sounding). I definitely know I am in the minority on the Fishman pickups, but they are really just underwhelming to me.
I unfortunately can't speak on the RetroActive pickups, but would like to try them at some point.
Cole
