Any Fatboy Unipivot Users?

Impressions? Seems like most are opting for the gimbaled version.
Smart move dhcod. Unipivot arms are inherently unstable. Look at the effort Basis and Graham put into their arms just to stabilize them. The Basis isn't even a unipivot any more. It is a bipivot. With very compliant cartridges there is some rational to it but with the stiffer cartridges we use today, forget it. If bearing "chatter" is a problem what is right about an arm freely rotation on it longitudinal axis? Some manufacturers like Lyra specifically recommend against unipivot arms. 
If you have a unipivot and move to the gimbaled arm you will notice the bass tighten right up and you will no longer have to mess with the azimuth all the time.
Thanks for answering a question I did not ask. I've used a few unipivots in the past and had none of these issues you speak of. I understand they are tricky for some but my Naim Aro, Moerch DP6 and JMW 10 all sound great and are easy for me to handle and set up. My cartridges do include a Decca so yeah, it's a nice match but I've owned many Lyras and never had an issue. I was asking for user reactions not for a religious discussion about tonearm design.
From a VPI dealer perspective, I can tell you on the last handful of VPIs I've sold, the customers have opted for gimbaled arms....with a few of those being Fatboys.  I personally like the gimbaled arms.
@dhcod , very interested in this thread as I echo your sentiment about unipivots, especially the VPIs and have settled on them in two different systems. With that said there has been a few VPI unipivot Fatboys come up for sale in the used market, one now on another site and I for one am wondering if the much higher price is justified in sound quality. I do believe they are a drop in replacement for my 3rd generation of 3D 10 inch arms. Enjoy the music
OK, most are opting for the gimballed arm because it is better, a lot better.
You can go to Lyra's web site and see that recommendation yourself. Perhaps because you seem to have been stuck on unipivot arms you might not understand the improvement you will get with a tonearm that does have adequate bearings and stability. All those tonearms you mention are seriously compromised. The Unipivot is  just a cheep easy way to make a tonearm unless you go at it like Basis and Graham. You certainly do not have to listen to me but perhaps I might be able to keep others from making the same mistakes you have. If you were happy with your arms why do you keep changing? I have had the same arm for 40 years and am just moving up now to an arm with wonderful bearings, neutral balance and vertical bearings at record level. 
@mijostyn I love your absolute terms. "A lot better" "Compromised". As if you've heard a single one of them in your home with your system. I doubt it. I'm replacing an SME M2-12r, not that I give two **its to justify myself to you. I change things because this is a hobby. Trust me, I have better ears, better trained ears than you do. I know about how things work together and how it's the harmony between components like arms and table and cartridges that makes for a satisfying listening experience. I also know that we all hear differently so you absolutes are pretty stupid statements. Everyone's frequency range is different. Everyone gets pleasure from different elements in those ranges. You make it sound like an absolute because of some BS you heard 40 years ago. I could go further but won't. I just want you to get the hell off this message board. **** you.
I have a VPI unipivot with the 2nd pivot mod (very inexpensive).  Provides the stability that cleans the sound and makes locking in azimuth, easy and predictable.
I went from the 10" 3-D Unipivot to the Fatboy Unipivot on my Classic Signature table.  Never had an issue with the original 3-D, and found that the Fatboy with the 2nd pivot mod is both more stable and sounds better.

Since I didn't have any problems it never really occurred to me to switch over to the gimbal. I also like the idea of finding a used arm wand down the road in case I'd like to do switch cartridge swaps, something you can't do easily with the gimbaled arm.

I'm sure the gimbaled arm sounds great and from what I've heard in forums, might be an improvement in the bass department. YMMV :)
What @myjostyn is referring to is the inability to repeatability, reposition the arm after cart changes and the like in the exact same spot where the pivot point aligns exactly in the receiving cup as before. Also if one doesn't very carefully/slowly handle the arm when changing records, this alignment can get off slightly.

If owners of the 3D uni haven't noticed this, they must be perfect or not paying attention.

I use the dual pivot with my PEEK film upgrade to great effect.
I have never had a problem with VPI uni-pivots.  Contrary to what has been written, they are very stable once you let them go.  I moved to the 3D arm and eventually with the dual pivot and a ruby tip.  Besides a small increase in SQ, it is far easier to set up, especially for azimuth which is now easily dialed in.  It also handles a bit more like a conventional bearing arm, but I could care less.
If those who couldn't care less are always seeking upgrades to their systems, why post "I could care less"!
I remember jousting with @tooblue over (nothing) a while back.

Oh yeah, "enjoy the music".
@slaw , if you would please refresh my memory, as I have the tendency to forget the trivial things in life. Enjoy the music
I disliked the JMW metal arms of the past. Had a terrible experience with the old unipivot on a scoutmaster.

Now have the Unipivot fatboy with dual pivot on a VPI Avenger Reference... and it is awesome.
If you think about it, the phrase “I could care less” actually means that you care and that there is some amount of caring that you feel that could be reduced. Better to say simply, “I don’t care”. But we all do care, or we would not be here to get into such ridiculous petty arguments with each other.

A search reveals:
Merriam-Webster treats the phrases couldn’t care less and could care less as synonymous, both meaning "not concerned or interested at all." "Couldn’t care less" is the older and more obvious phrase grammatically, but it has been confused for so long that both are now defined.