Really curious about this, have been close to pulling the trigger a few times.
Currently have a g900 I adore
I have high hopes for this thing:
http://www.swiftpoint.com/Z.html
So I've been using the Swiftpoint Z for a few days now and I really like this fucking mouse, goddamn. Was using a Roccat Kone+ which was nice, but the way the button setup is on this makes it another level for some games.
There's 3 buttons on each side of the mouse, so there's the main LMB, then acap closer to the body and a smaller cap right close to the body. Sounds awkward, but the three parts you can just hit with different parts of your finger when needed. There's a further two thumb buttons on the left, clickable mouse wheel (also clickable by nudging it left for a quick action in a game) and two other buttons to the left of LMB. It all takes a bit of getting used to with the three buttons, but when it clicks, it clicks.
There's also pressure sensitive mouse buttons which you can configure how you like based on % of force. You do have to try to get 100% and it vibrates when you do, so I have it setup for Roadhog on Overwatch where fire is any pressure, but 100% is melee which makes it a great way to hit the shot/melee after a hook.
That's it button wise, and while I haven't used all the buttons a whole ton for gaming, but in Widows, it's fantastic. The left top cap acts as alt+tab and you can move the mouse left and right to pick a program, while the right one is ctrl+tab.
The other functions I've not used that much so far are motion control. I played around and it is very accurate and will be great on flight sims. Going to try out Battlefield in a bit. There's also force feedback and by lifting the mouse up and to the right, it goes into a config mode to set DPI or change profile on the fly. Aesthetically, there's an RGB logo on the back and an OLED screen on the front left which shows what you want it to.
Complaints are that the driver program to configure it all is kind of a mess right now and the vibration when going into config mode feels cheap, like something was rattling, although all the other vibration feels fine.
This is easily the best mouse I've ever used, but I got this at $149 on Kickstarter, which feels very reasonable for a premium, high featured mouse. Looking at their website, they now want $229. I don't know if I would pay that for it...