Hello, all.
Finally read through this entire thread. Lots of great information. Damon, I believe it was you on the Facebook page that originally talked about the auxillary pack idea? I remember seeing that a long time ago. I finally tried it out a few weeks back, then decided to read up some more on the subject. I couldn't find your original Facebook posts but I did find this thread. Glad I did as this looks like a better overall discussion.
I'll have to post some pictures of my Inspire along with my charging and discharging setups later on. For now, I'll add in that I'm using only 1 auxillary battery as opposed to two in parallel. The two setup looks awesome and I like that mount that Damon developed, but a single battery appears to be less intrusive to the camera, less wires and less expense. I use Autopilot for a lot of video and am constantly turning the camera 360 degrees. So far, my setup has not had the battery in the way of the camera (camera view, that is). Either way, both setups appear to work just fine depending on your application.
The battery I'm using hasn't been mentioned here yet, but I've found it to be a viable choice. I've been using the 6S, 50C 5200mah Lectron Pro.
Amazon.com: Lectron Pro 22.2 volt - 5200mAh 50C Lipo Pack: Toys & Games
The discharge properties of this pack have been impressive thus far and I never get the "low propulsion due to low voltage" warning. It has consistently been depleted to 14% remaining while the main pack I've stopped at 10%. I've really been happy to see that I'm getting the max use out of my batteries (or as much as I can). I'm still in the process of "fixing" my DJI packs with the reset method to get their capacity back. Pain the neck, but I've finally gotten one of my packs all the way back to 5700.
I haven't done any hover tests. I just assume fly around the way I would for any other flight. So far, I've been getting a consistent 21-22 minutes of normal flight time while using an X5 camera. Not really close to the crazy numbers some of you have gotten, but I've been more than pleased considering I was getting 11 minutes with a TB45 and 13-14 minutes with a TB48. Having 20+ minutes of "useable" flight time for video with the X5 is amazing. I don't feel like I'm wasting my pack when I want to stop and change settings, so this modification has been amazing to me.
I'm currently using RCTimer 1448 props. These are exactly the same as the T-motor 1448 at a fraction of the cost. Same weight, same stiffness. Probably came out of the same factory. They've worked perfectly for me for a very long time. As for flight characteristics, I have noticed the extra weight on the craft, but it really hasn't affected me adversely. I think it still flies smooth, just a bit more sluggish with acceleration. Top end speed still hits low 40s. For those of you that might want more typical flight characteristics that you would see without using aux packs, try the Tarot 1455 props. They are cheap and have a lot more punch/lift at the cost of flight time. I dropped down to 18-19 minutes of useable time (still great in my eyes), but the Inspire flew similar to a normal setup.
For those waiting on the Multistar LiHV packs, I just noticed HobbyKing has them in stock again. I ordered two 6600 packs from their international warehouse (still none in the US warehouse). I'm in the US, but I didn't want to wait for the US warehouse as it is unknown when they will get them. At least now I know I'll have them in about 2 weeks. Definitely looking forward to possibly getting another 2 minutes. That would be great. In addition, and I never knew this about HobbyKing, if you leave your browser open on one of their products for sale for about 5 minutes (maybe about 10?), a message pops up with a lower price for the item. Cool. Never knew that. I got both of my packs for $10 less ($10 off both packs) and $16 off the LiHV charger I picked up from them as well. Nice.
I'll post some pictures later and I'll report back when I get the new Multistars in the mail.