My friends and I have been flying quads for years and finally decided to jump from analog to digital video. This is our first DJI build. I am so happy with the outcome that I had to post it to encourage others to try it. We have built two of these so far, and a third is on the way. Let me first tip my hat to others who have made similar builds and posted here for us to learn from. We are mainly a group of park flyers, so our design goals were to have very reliable video and control links within the 1000'x700' park we fly in, be non-threatening to other park goers, maximize performance, and have great video. To that end, we tried to keep it light because a lower disk loading means a quieter quad, but also have enough throw weight and power to be able to fling it effortlessly over a medium sized tree. We also strove for a 5 min flight time.

Components:
We chose 3s batteries with FPVCycle 1304 motors after much research. We felt that combo should have the power and efficiency we needed to haul around a Vista. Our runner-up motor choice was the Amax 1303 because of their lower weight, but in the end we went for slightly more power with the 1304. We picked the Hornet HD frame because of its light weight, top mount battery, and Vista accommodation. We were concerned about it being too fragile, but TorqueFPV beefed up the arms a little, and we are building light, so we hope it will be tough enough. We were torn between using the DJI controller or some other long range solution. We settled on the Ghost system because it seemed to be the most flexible and low latency long range system right now for our existing radios. Crossfire was tempting also, but the amazingly tiny Zepto rx and Qt antenna tipped the scale towards Ghost. Previously we had all been flying Taranis w/ xm+ receivers, and we kept getting occasional failsafes even just a hundred feet away. The long range control link may seem like overkill for a park, but we were actually shooting for excellent control link reliablility within a park. We replaced the stock Vista antenna with the TrueRC singularity for additional weight savings. Finally we chose the JFEMCU F411 AIO Pro FC for its low weight, and high current ESCs. 35 amps is way more than we need, but if, after flying it, we felt we needed more powerful motors like 1404s, it gave us the margin to do so. We were trying to keep it under 130g AUW.

Build:
The 1304s were a great choice on 450 mAh 3s packs with the 3018 bi-blade push-on props. This is a very efficient combination, but we were concerned that the motors, being large diameter for their rather short length would suffer from poor response time (as compared to a thinner, taller motor choice). This turned out to be a non-issue. The quad has no problem responding quickly to prop wash to mitigate it as much as any other quad I've had. De-casing the Vista and removing the blue goo was arduous, but necessary to meet our target weight. I suggest you mask off all your Vista connectors before attempting this. That stuff goes everywhere. We printed the 3d vista parts that DadFPV made available on Thingiverse here. We then modified the spacers slightly for a better fit, and added some washers to go outside the canopy for better securing the camera. Those are posted on Thingiverse here. The fit of the vista boards on the 3d part is tight, and requires a bit of electrical tape on top of the ribbon cable to prevent shorting. The 330uF 25v low ESR cap worked perfectly for us (no need for anything bigger), and the FC board even has mounting holes for it. I ordered some replacement screws for mounting the motors because the m2x5s included with the motors were a bit too long. I bought titanium m2x4s to save a little extra weight. The FC has 8MB of blackbox storage, so tuning was fast and easy. It also has 9v regulated power pads for the Vista, which is great. We were excited to see that our weight came in quite low, although we did spend a bit more on some replacement parts to achieve this.

Flying:
The vista does get hot when powered up but not flying. We try to take off within 20 or 30 seconds of powering up. In flight we have had no heating issues so far.
It turned out to be sort of quiet, sort of not. If you just cruise around, people in the park don’t even notice you. They do not appear to be threatened in any way. I would say it’s about as noisy as our Diatone 229 Cubes on 2s. So in that regard, we met our goal. However this quad has quite a kick when you hit the throttle, and it does rip like any 5000kv 3s typically will. In this case people around the park might look up and ooh and ahhh a little. Thankfully it's much quieter than any of our 4s builds.
The efficiency of this power system is great. We routinely get over 7 min just cruising around the park, or around 5 min of modest freestyle.
The controllability is awesome. It is my nicest flying quad yet. Maybe FCs are getting faster, or Betaflight is getting better, but this flies like a dream. The sense of positive control (and the great HD video) makes it feel a lot like you’re flying a simulator.
Here is a flight video from our local park. I tried to show that our setup has the range to get anywhere in the park with ease, and the performance to do more freestyle than I am currently capable of.

Closing Thoughts:
I dont think any of us has any regrets about any of the parts we chose. There were some buildup issues we had to contend with, like screw sizes that didn't match with how we intended to use them. And the Hornet canopy is designed for the original DJI camera, so I still need to do a little work on it to increase the available camera angle for the Nebula. Stuff like that. But it was a rewarding medium skill level build. Not a beginner build. It was also pricey, especially considering cost of the goggles, but honestly the FPV experience is just so much better than analog. I really didn't think we would get to a lightweight digital solution this fast. As recently as just 3 years ago everyone was saying how long it would take to replace analog. And here it is. And it's amazing! I hope you try it.