Ok, what we are dealing with here is pretty much a "limited use" adapter designed for a specific purpose. As we know, the issue with the new iPhone 7 and 7 Plus phones is that there's no longer a 3.5mm headset jack. Which now limits us to using the single lightning port to both use a wired headset and to charge your phone, leaving it impossible to do both at the same time.
Enter this Belkin Lightning Audio + Charge Rockstar adapter. Barring the name, this is perfect for the specific use that it is made for. Basically, you plug the adapter into the lightning port of your phone (or iPad, or any device using a lightning port) and it works as a splitter, splitting it into two lightning ports. This allows you to both charge and listen to audio, as well as phone calls, at the same time.
In my testing, it worked flawlessly. I called my friend using the adapter and he said I sounded normal, no difference between having the adapter and not having it. So there's definitely no quality degradation in calls or music. I also had zero issues charging the phone. I used both official Apple lightning EarPods and Lightning cable, as well as an Anker Lighting cable for charging. Also, it doesn't matter which port the charge cable or the headset is plugged into. Inside the packaging, however, it does state to not plug two headsets or two charge cables in simultaneously. This should be a given, but I suppose they put that on there for their protection.
I have heard that some people cannot use the speaker while this is plugged in and on a call. I tested this and I had no issues. I was able to transfer from headset to speaker and back again, perfectly.
As far as aesthetics go, I would say that this is extremely close to Apple build quality, looks and construction. The cable between the adapter and the lightning plug is thick and very high quality. The Belkin logo is branded on both sides of the lightning plug that goes into your phone Because of the thickness of the cable, it is very stiff and doesn't bend freely. This could be a pro or a con, depending on your personal preference. I, however, felt it was a little TOO stiff. But to each their own. :-)
Why am I giving this only 4 stars then, instead of 5? Well, 3 things, really, First, this acts as charge and audio ONLY - so you cannot do data transfers via the Lightning cable through the adapter. Second, this, again, is a very limited use/specific scenario product. If you use bluetooth earbuds/headphones (or the new AirPods), then unless you plan on using wired at all, this is all but useless. Third, the price. At $40 a pop, this is way overpriced. $20 - $25 would be more of a "sweet spot". At the current price, however, I cannot recommend this unless you ABSOLUTELY need to be able to charge and use lightning headphones at the same time.