Problems with recent firmware update

R7000, current Firmware Version V1.0.6.28_1.1.83  

interesting I got the upgrade notification email on 2/2/16 AFTER upgrading to V1.0.6.28_1.1.83 on 1/30/16....

So here is the sequence of events and issues I've seen with this router:

1. purchased the system Sep-14, spent close to 100hrs with Netgear CS trying to optimize the router to be able to communicate with different devices in my home. It took 2-3 months till all my devices got acceptable communication and worked great till...

2. about 3 weeks ago, out of the blue, at least nothing I did, my Sami Note 4 (problem not seen with my other devices like a Sami S4)started having issues sync'ing with my Comcast email using exchange when on WiFi, not an issue when in cell mode. Note 4 is connecting using the 5G band. Tried deleting the account, changing the ports setting on the phone etc..., no change, the Note 4 refused to consistently sync with Comcast (occasionally did worked).

3. on 1/30/16 after doing some research on the net I decided to look into the router setting and found that I was on an old 1.0.3.80 so I decided to upgrade and see if helps. Well the email sync issue seemed to have solved immediately after that and work ok that day, but next day started having the same issue again. Not just that but my Note 4 (again not see on the other mobile devices) started having an additional 10-30s delay in loading any page/content etc. from the internet, again only on WiFi.  Speed tests were equivalent before and after the firmware change (~40mls, 80-110Mbs). Again on cell mode all pages were uploaded instantly, but on WiFi mode it adds another good 10-30s uploading anything. I've tried changing all relevant settings (enabling smart connect, Preampl, channels, 2.4 vs 5G, enabled and disabling Smart connect, BEAMFORMING, AIRTIME FAIRNESS etc... I spent several hours on different options. Note 4 is connecting fine using the 5G band and at speeds >500MBs.

4. after reading issues reported here with the new V1.0.6.28_1.1.83, yesterday 2/6/16 I decided to downgrade so I tried all the version one by one down to 1.04.18, same issues !

Contacted Netgear, they wanted $200 or more to extend service, which is an extortion for a $200 router and that this seemed to be a fwr issue, I told them no thank you ! They did imply that this could be an optimization between different devices/bandwidths/channels tec., nothing that I didn't tried before. 

I will try a factory reset and see if it helps, but the ROI on this premium router turns out to be very negative, if I had know that Netgear will turn their back to customers after charging premium for their unit, I would have gone with other known brands. I had the WRT54G for many years (still works) and never had an issue with it, good service.

If you have other suggestions pls. let me know. 

Thanks !