A couple years ago, I was torn between getting the Quad Cortex or the FM9. Last month I got my invitation to purchase the FM9 Turbo and went with it, figuring that if I didn't like it I could flip it, and then go for the QC instead. Though it may be overkill, so far I'm really liking the FM9 and will be keeping it. I've always used the SVT bass rigs as my benchmark and feel that those are totally up to snuff on the FM9, with an assist from
@dr bonkers for some of his 3rd party cab IRs (the Mesa Boogie® 8X10 RoadReady™ among others, is an excellent tone flavor). IMO, the cab IR is a key ingredient in getting much of the sonic essence of a rig. Though FAS doesn't have many bass amp tone stacks to choose from, the cab IR can get you much of the way there which helps alleviate the issue of variety, even though I'm perfectly happy with a good Ampeg tone.
True, I've had to digest the fact that FAS is not too interested in expanding the bass selections. In this department the QC is clearly head-and-shoulders above what FAS delivers. Still, I've been following the progress of the QC on this and other forums and didn't feel 100% comfortable with it for various reasons...too slow in maturing to initial expectations. Much of what lives in Fractal devices is based on a long track record of sussing things out, and IMHO they've got much of it right. That Fractal is local shop also helps with confidence if I ever need service.
I'm approaching the FM9 Turbo for performance using one or two "kitchen sink" presets, which wouldn't be possible with the FM3, and using a mixture of Scene, Channel, and individual custom "per preset" switches. Bass instrument changes and tunings require adjustments to level and EQ via switching, as well as scene changes for fundamental amp tone changes (via amp/cab Channels). I have a Drive block set to 4 channels, with a switch that scrolls through 4 settings (Klone Chiron, currently) to take me from clean to full-blown heavy distortion. I do wish there was a SansAmp BDDI model as I've never bonded with the Darkglass B7k, much as I've tried. Tuner is set for pass-thru while playing and full bypass quiet tuning (switch press-hold).
Anyhoo, I've no regrets with the FM9 Turbo. It's a luxury pedal for bass, no doubt, but knowing that I can have all my critical functions and effects needs accommodated on one unit (even though the bass amp models/drives/cabs are limited), programmed the way I prefer with almost no limitations, is something that is quite valuable to me. Currently, I'm working on a cello sound based on the shared preset that's been on the forum recently.
https://forum.fractalaudio.com/thre...some-free-irs-and-a-sloppy-rush-cover.191451/
Amazed at how realistic this sounds.