Bought this frame late last year but only got the chance to get to it recently (spent a lot more time than expected tuning a 10" quad :) ).
This is my first foray in the HDZero world - and the new HDZero stack literally came out as I was looking around for a stack.
I also have a few 8S batteries now so it will be interesting to see if there is any increase perf using those with 'standard' 6S 2020kv motors.
Build is insteresting as different to the more traditional race frame I did earlier - the whole electronics stack & VTX are together sandwhiching the top plate that you slot into the frame assembly.
All is left is to solder the motors and close with the bottom plate and you are done.

I got caught out by the change of pin outs of the VTX Race V3 - the sort order of the cables matches perfectly the FC plug... apart from the 180 degrees reverse order (new Race V3 will have the new pin out). Only found out once the whole assembly was completed so I tested putting the main stack out, apart and back in and I have to say it is quite a handy setup to work with - takes a bit more time than a traditional setup (stack on bottom plate and vtx on top plate) but should not make much difference once I'll get use to it.

I was originally a bit worried with the assembly steps - I did start putting an AOS UL10 together and the assembly can be quite finicky as you need all the slots to match perfectly. On the Fox frame though it is incredibly easy. The tolerance and finish of the carbon feels so much more precise - not had to touch anything with a file and assembly snaps and stays together without any trouble even without any parts screwed in. I am impressed.
They also recommend using nylon stack screws - and there is no space for any 'golden nut' - the top plate tolerance for the M3 holes is quite tight though. Never had a frame set this way but followed suit.

The design means the quad is light (491.1g with a Tattu V5 1200mAh) and super compact with the props overlapping - and quite aerodynamic too so hoping for some good perf out of it. First flights went very well with the default Karate tune - it oddly feels extremely well tuned/locked in already but I believe this is the mix of the undeniably good quad perf and the HDZero system low latency (compare to the Walksnail setup I am used to) skewing my judgment. I plan to do a few back to back sessions soon to compare it to my other race quad (AOS5R).