I present my first 6" and 6S build, Cloud Errant.

The Concept
I wanted to create a freestyle drone capable of smooth flow and a stable feel. Reading up on all the hype about 6S, I felt it would be fitting to use it on 6", especially since there has been so much praise for the T-Motor F40 Pro II's. I knew 6" was the crux of acheiving that stable feel, since theoretically it provides more efficient lift and handles propwash better.

The Build
I looked at a few frames for this build. I have a Reverb, and while it's a great frame, I didn't think a 6S battery would fit comfortably. I also felt it was prone to jello in GoPro footage- something that I tend to have OCD with. The Raggio Lungo by Falcon Multirotors was enticing too. I ended up buying that frame and am planning a 7" 6S cruiser (it's a beautiful and big frame). I saw a couple of comments about Kinetic Aerial's Vector frame, and was immediately hooked. True X, 5,6, or 7" arm options, slammed body, and the ability to run a Steele OSD PDB without modifications. This frame also comes with a plethora of TPU options for antennas, GoPros, and frame protection. I found it to be very high quality and well thought out. I especially like the ample room in the back for an Rx and VTX to mount on a G10 plate.

The combination of Steele PDB and KISS V2 components makes for an easy, clean build. I have both a Nano and Micro V2 Crossfire Rx, but decided to use the latter for one important reason: modularity. I prefer the JST pin over the direct solder of the Nano because it's easy to remove and service. The build is also fully waterproofed using conformal coating and liquid electrical tape in key areas. I'm ashamed to say I haven't known about the Ummagrip earlier. It really is fantastic at keeping the battery stable and equally great at providing a bed for the GoPro, dampening vibrations.

The Maiden
Very few times has a fresh build wowed me on maiden. This one did. It felt very familiar but new at the same time. Kept at stock PID's, the quad was extremely stable and buttery with fine input. It maintained crisp lines and was locked-in in places where every 5" would have oscillated in propwash. There was a controllable floatiness to it that I really enjoyed for my style, and also had an excellent throttle curve. I felt in total control of altitude in tight areas at different speeds; it definitely has a higher cruising speed than my 5".

The best part was the torque. The combination of these motors and props along with 6S voltage allowed instant change of direction and pull-outs from diving. It all meshed together to bring the most locked-in quadcopter I've ever flown hands down. All that needs to be done now is a proper tune. I term and D term can be raised a bit, but I want to experiment with P to understand the limits of this build.

A couple of points to consider:
1) Flight time with moderate freestyle was about 4:30-5 minutes, with motors coming down much warmer than I ever had with 5" builds, but not at all considered "hot." I don't know if this is because of 6S batteries. Peak amp draw was about 125A.
2) The F40 Pro II kV of 1600 is equivalent to 2400 kV on 6S and I feel it's a nice balance. The props seem to hold on high throttle without flattening out but I did not push too hard on maiden.
3) I flew a total of 4 batteries. I clipped some branches on the second pack and sustained minor dents on the outer reaches of the blade. After that, there was slight jello, so maybe these props are more susceptible to aero changes upon damage. Keep in mind that these are stock PIDs in full sun and no ND filter.
4) This is the first build that I've hard mounted the KISS flight controller. It has been suggested this actually helps keep jello down. I think the combination of motor TPU soft mounts, Ummagrip under the GoPro, and hard mounting the flight controller all contributed to such smooth footage overall.

Here is a raw clip of the maiden flight. Stock PIDs and easy flying.

The Verdict
I couldn't be happier with this build. I love how the skin wrap and hardware came together for a beautiful finish, and I especially love how it flies. I think there is definitely something to the 6S hype, in that battery sag is noticibly more predictable and less throughout the flight. I'm getting similar flight times and as shown in the clip very smooth footage. These are the kinds of builds that make you appreciative of how far the hobby has come in only a few years!