Hi all 
I’m new to freewheel unicycling. I’ve got my first 27"5 freewheel two days ago. I had already tried freewheels a few years ago - a 24" I hadn’t been able to get on and a 27"5 I had been able to mount after a few tries - but I had never tried to ride it for more than a few meters. So it’s a whole new adventure for me! 
Note for the following: I describe myself as an advanced road, muni and freestyle rider. I basically ride unicycles everyday and everywhere.
My unicycle is basically a QX RGB with a Nimbus Drift hub and a Kenda Havok tire:
First of all, it’s pretty hard to get on that crazy unicycle. I have tried to get on it with a prop. It was really wobbly. I then started to simply jump on it. And it worked much better - I simply had to remind that the front foot should land on the pedal before or at the same time than the rear foot. Since then, I have tried less than an hour and I’m now able to do a static mount on a flat road or on a negative slope. It’s much harder on a positive slope. So I have to jump when being on a positive slope.
Regarding the brake coast, I find it really easy as I was already able to brake coast on a fixed uni on off-road trails. As my other 27"5 uni is an old Qx with the same brake, I’m used to it’s power and modulation. It helps a lot!
I have not tried to coast without the brake yet. As I already master regular coast on a fixed uni, I should be able to coast on a freewheel uni. At least I hope so.
My main goal in buying a freewheel uni was to do some muni on it. We are currently under lockdown in France so I can’t go for a long ride - 1 hour max per day - but I have the opportunity to live on a hill with some great, close and easy trails. So I went for a few km of off-road riding with my girlfriend on her 26-fixed uni. She’s still in her learning period so we were basically at the same point and it was really enjoyable for both of us! 
I have been able to brake coast for all the negative slopes, some of them a bit bumpy for a few dozens of meters. It’s really different of fixed muni but so cool! I’m looking forward to go for another ride on harder trails!
Something I have thought about is the similar behavior compared to a Schlumpf hub: when shifting on a geared hub, there’s little time of freewheel and a clack. That’s the same on a freewheel when switching between pedaling and brake coasting. I think being used to ride a geared unicycle makes it easier to go on a freewheel uni.
So, what’s next? I’d like to learn how to jump and do some drops. I don’t know whether the hub will resist or not. If it breaks, I’ll wait for buying a Qaxle freewheel hub - I hope it doesn’t break to soon!
I have to work on my mounts, too. I should be able to get on the unicycle at a success rate of at least 95%.
Last but not least, I should be able to coast without breaking. It’s probably the hardest skill of my list, but one of the most useful, too.
BTW, thanks to all of you for having gathered so much information about freewheeling. It’s really great to see videos and reviews of your training. @AJ_KJ and @waaalrus are a big source of inspiration for me. I hope I’ll soon be able to do what you already do! 
PS: as I’m fond of clipless pedals for road and muni, I’m wondering whether it could be useful for freewheeling but I haven’t figured out the answer. It looks much more dangerous than on a fixed uni because of the movement needed to disengage: the pedal could come with the feet as there’s little force against the upward move. Has someone already tried it? Any pros/cons? Guess I’ll try once I’m confident enough with the freewheel!