Well, my impressions/ experiences so far. I cannot tell how 'good' it is, since I cannot compare to anything else, hence I'll concentrate on the negative aspects, it's more like nitpicking, so don't jump to conclusions based on the negatives
- Extremely portable. This is actually very important for me, some planes in this class have glued tail surfaces, hence a pain in the b*** to transport them. This is why I ditched the Easy Glider and started looking for the Graupner Junior S, but decided to go for a plane with better acrobatic capabilities. The Fox comes in a 103x21x16cm (both RTF/ARTF) box

which is perfectly portable, even in smallish European hatchbacks. The horizontal stabilizer is fixed with one screw/nut in less than 20 sec, and the piano wire has to be tightened at the servo (in the canopy). This should be a snap-on system of some kind, even though making some marks on the wire makes the trimming easy enough. Secondly, they could have added few extra, or better pieces of foam to transport the wings safely instead of loads of bubble wrap. This would have given this plane a truly Unique Selling Point in the market.
The hatch closes with a fairly weak snap-system, not reassuring at all, or at least if the puny rubber bands which are supposed to hold the battery snap, the battery
will fall out in inverted flight and result in a crash - as demonstrated by a guy on YT

This isn't a big issue, just add some velcro and the potential problem is sorted.
The plane can be flown with different sized batteries, but I mixed up some figures with the Windrider Fox, hence used a substantially larger battery (2.2Ah instead of 1.3Ah) which wouldn't necessarily be a problem, but since my battery was heavier I pulled it farther aft, which probably closed the ventilation channel. The result, On its second flight, 5-6min into the session, I had a semi hard crash, I wasn't sure why, I sort of lost control, after all I am a noob and it was slightly windy with some turbulence, but noticed the ESC was very hot (too hot to touch). I removed the heat shrink tubing and the plastic something between the board and the cooling plate, and applied a fair amount of silicone thermal paste. I'll salvage a ribbed aluminium cooling plate from a mother board og GPU in the future, but I definitely recommend everybody to watch out for the ESC. Secondly, I added a UBEC, actually it's a small 10A ESC with BEC, but now the power supply to the Spektrum AR7000 has redundancy. After its 3rd flight, I checked the temperature, and the ESC was still VERY hot (longer flight), so I believe the crash was due to power shortage (Spektrums are prone to fail (reboot) even due to minimal voltage drops).
The third issue is the fixture of the carbon rod in the wing, two screws are used to 'clamp' the rod at both ends in the wings. The screws are fairly small, hence afraid of stripping them, I might haven't tightened them enough, since after the 3rd flight I could see the wings were starting to separate... I've ordered some rare earth magnets and hope these will solve the (potential) problem, otherwise I'll probably drill a hole through the wing and carbon rod, and use a small nail and magnet to fix the rod.
There certainly is some flex in the wing, but it doesn't seem to be an issue AFAICT. If you are planning on 50mph slope soaring, then you'll have to add some carbon, but otherwise it looks adequate. The only carbon I'm going to add will be on the underside of the wing tips (for concrete/ asphalt landings).
Generally, it's a very nice plane, good looking, the foam is fairly smooth, not as many injection point as the Windrider, but if you are interested in looks, better sand the injection point down and give it a full coat of foam safe grounder. The folding prop is a bit flimsy, yet it survived the crash, which cracked the firewall plywood. I had to glue in a another one, but I'm very happy that the crash didn't cost me a penny. I cannot comment on the performance, the pilot (me

) is the bottleneck in my case. Btw. the best thing about it is the sound! I let it climb for a few minutes, and then let it go into a dive, over my head, that SOUND! YAY!
I tried to test the roll rate, but that manoeuvre didn't turn out very well

I was saved by the altitude, so I'll wait a few packs before I try that again.
All in all, I'm VERY pleased with this plane, a plug n play plane for less than €100 delivered is a steal (in the EU at least).
Feel free to ask.