As a fellow FM3 user, a lot of the benefits you would get from an EMG 81 can be dialed in the virtual gear and settings. The bigger issue is having patches set for active or passive pickup output level.
Never knew about the EMG preamp change. Makes me want to look at the dates of my pickups. I get most of mine from EMG outlet store on Reverb. Seems they're pretty low on stuff now. This response got huge as I am thinking of some pickup swaps in my near future.
I rarely see people mention this: Isnt one of the big things is the humbuckers are in parallel as you can't run EMGs in series? As a bass player I think of the classic Stingray MM in parallel. Very punchy, and clear - yet a bit choked down low. Compare humbuckers in series vs parallel. The Stingray preamp (which is a very complicated circuit - unlike the EMG) buffers the loss and scoop and then you can add back in bass and mids and the Stingray is a force. So in my limited understanding, an EMG humbucker you have two epoxied isolated coils ran parallel into a preamp that initially was low output and balanced, then the preamp boosts it back. This dynamic is what sounds great distorted, and why some feel they're sterile and lose dynamics. Personally, I think you're technique/playing style can accomdate and it not be a huge deal. I can understand someone used to PAFs or classic single coils plugging in for a few minutes and hating EMGs.
I have tried to love the Fluence (almost have tried all sets) but I have never sold off my EMGs. Seems when I want a passive or active, I have a specific idea in mind. Fluence is an interesting bridge of the two technologies. They're worth checking out. The 3voice Classics maybe the ultimate versatile pickup. I still want to checkout Duncan's BMP-1 that is part of the Gus set. The idea of an external preamp that can turn any pickups into an active system seems appealing. I am surprised I rately hear anyone talk about it. I have a duality set that I want to try mag swapping but need to confirm I wont break anything first.
Admittedly, I have been a fan of EMGs since I got an ESP as my first 'wow guitar'. At that time I was running around in hard rock / metal bands with hi gain. They do respond to pickup height and technique. They amplify your playing - so if you're sloppy it can make you sound terrible. The best thing ever is the tech convinced me to swap around EMGs instead of just keeping the 81 in the bridge and 85 in the neck. I prefer the the 85 in the bridge for everything except the lowest, crushing metal. My favorite setups for HSS are 85 / SA / SA or 89 / SLV / SLV or for HH 85b / 60An or 85b / 89n
I actually dig the single coil sound of an 89 over the 89R. The 57TW is great 89 replacement too.
The 58 is an amazing pickup to try for more classic tones. The local Guitar Slinger / Tech swears by the Tele set and his tone is admired.