Agreed...I am "temporarily" on a Note 5 as I wait to see how Verizon handles future Flagships and when battery life on Windows 10 mobile settles down on my ICON. I love having a stylus handy and man, this phone is a beast.
FYI, W10 Build 10572 works GREAT on my Lumia Icon now, but there is a trick on how to make it work, and it's rather lengthy, but my Lumia Icon now works better then Win8.1 did. You'll also want to back up EVERYTHING, cuz you can't do any of the restores to your phone - it has to be all new installs of apps.
1) Reset phone back to factory settings Win 8.1 - DO NOT RESTORE
2) Install Windows Insider Preview app and run and choose "Fast Ring"
3) When it reboots it will install Win10 Build 10572 - DO NOT RESTORE
4) RESET to factory settings AGAIN - YES - Reset Windows 10 to factory settings
5) When phone finishes and reboots, reinstall Windows Insider Preview app and run, choose "Fast Ring" again
6) Phone reboots again and installs Windows Insider Preview version of OS
7) You should now be on Windows 10 Insider Preview Edition Build 10572 in factory settings.
8) You can now put all your files and folders back on the phone.
9) MANUALLY reinstall all apps from the store
10) Enjoy VERY LOW battery usage, cool phone, smooth apps, no crashes, etc., etc.
NOTE: While you are installing apps, updating phone, etc, the phone will be warm to hot, but that is because you are working the processor and antennas A LOT! Once you have all apps installed, updates finished, etc, you will be VERY HAPPY with your Lumia Icon on Win10 Build 10572!