I can't answer for PH, but I also have a Joey.
In my case it is a long tale that I will try to keep short, with some disappointments along the way.
I bought the frame and fork to build up in 2006. All folding bikes are a compromise, some emphasize better portability at the cost of the ride and handling, some emphasize better ride and handling at the cost of portability. The Joey at that time was marketed as the best handling folder that you could fit into a case that would not incur airline oversize fees. I previously had a job that involved a lot of travel and I would have liked to have had a folder at that time, but by the time I bought the frame and fork and built it up, I was not traveling for work much so the purchase was more to fulfill a past desire, not a current need.
Then after I built it up, I tried to buy the airline case for it. That was when I learned that the case was not sold in USA. I asked the dealer that sold me the frame about a case, they said they had a nice case to sell me, but it was not the case I specifically asked about. I decided to wait until I was near that dealer (~400 km away) so I could look at it instead of buying it and having it shipped to me. Good thing I waited, their case was huge and would incur oversize charges. The dealer than said that there was no case that the Joey would fit in that would meet USA airline size criteria. At that point I realized that the case that Airnimal suggested for the Joey was not sold in USA because the USA airlines all had more stringent luggage sizes than British Air. And the marketing was oriented towards British Air flyers, not anyone else. That was when I suddenly had a huge case of buyers remorse.
So, for the next decade the Joey was rarely ridden, there was no way I could recover even a small fraction of my costs if I tried to sell it. I stored it in my truck in case I wanted to ride a bike somewhere that I had driven to.
Then in 2016, when I unpacked my Nomad Mk II with S&S couplers from the S&S Backpack case, I looked inside that empty case and decided to try to fit my Joey into it. It would take a lot of disassembly, but I could make it fit.
So, I finally learned that I had a folder that I could take on an airplane after all. This was a decade after I had first built it up. And by now I was retired and almost never flew anywhere anymore.
Two years later in 2018, two friends and I all signed up for a van supported bike trip in West Texas run by Adventure Cycling Association, each day we would ride our bikes to the next campground while the van would transport all our gear for us. The three of us flew on an airline that gave you two free checked bag allowance. On a whim, I decided to take my Joey on the plane, it would travel for free in my S&S Backpack case. It took as much time to pack it as it takes me to pack my S&S bike, a few hours, but it worked. Instead of taking their bikes on the plane, the other two shipped their bikes ahead to the motel, they had road bikes in bike boxes. Rode my Joey for that week, everyone else rode road bikes or touring bikes. And my Airnimal Joey was almost as good as my other non-folding bikes. It has a bit of flex in the tall seatpost extension. And there is flex in the steerer tube extension. But after several hundred miles, I got used to that flex, so not a problem for me.
Since then I have occasionally considered taking it on a trip but have not done so. Occasionally take it out of my truck and ride it. Just yesterday when I dropped off my truck to a repair shop to do some maintenence, I rode my Joey home, plan to ride it back to the shop later today.
Airnimal made a lot of changes since 2006 when mine was built. Mine is rim brake, and I learned the hard way that my tire size is extremely rare, so I have bought spare tires to keep in storage. They apparently changed the chainstay design later to fit wider tires so there are more tire options on the newer ones.
Mine is derailleur, not Rohloff. I can't fit a front derailleur to mine, I use a Sram Dual Drive for wider gearing range, that is a three speed hub that can take a cassette, thus mine is a 24 speed bike with an eight speed cassette. Newer Joeys can take a front derailleur.
A few photos.
1 - The bike packed in my S&S Backpack case. I even had to remove the crank arms to make it fit. Thus, not a quick one to pack.
2 - That trip in West Texas was hot and dry, I carried two water bottles, one liter each on the frame plus more in a saddle bag.
3 - The Joey in the motel room, the first fold takes less than a minute. I folded it to carry up the stairway to the room. To fold it you first remove the front wheel, the rear wheel goes into the fork.
4 - When I store it in my truck, I put it in a larger bag, I basically pack it like in the photo into that bag. Only takes a couple minutes to pack it that way into a storage bag. The pedals are not shown in this photo, I use MKS EZY removable pedals that are quick release. As shown in this photo, it took no tools to break it down to this size.
Although I have not enjoyed it as much as I thought I would, for some people that would find a need for a well handling bike that folds down to a slightly more compact size for commuting or for taking on a commuter train, I can see where they would have gotten a lot more use out of it than I have. For a small number of people, this would be a great bike.
In my case I probably should have bought a Bike Friday and the standard Samsonite suitcase that it packed into instead of the Joey. But, we live and learn.
ADDENDUM:
The Sram Dual Drive is no longer in production, but I have heard that Sturmey Archer makes a similar hub. I am using a Sturmey Archer bar end shifter for my Dual Drive, is indexed just right and works great.
I use drop bars and bar end shifters with my Joey, but I think most Joey users use flat bars which would be much more compact when folded.
