[Q] Which firmware for HTC M8 topic

i bought new HTC M8, however it in 4.4.2 and i check OTA, it said that my rom had modify so i can not update OTA
The current situation of my HTC M8 is : Unlocked bootloader, S-off, Super CID, TWRP recovery

• Software number :1.54.709.4


• Baseband version/Radio : 1.15.2133156


• HBOOT : 3.16

I want to flash viper 3.2.1 however the requirement is FW must be 3.x.x, if lower than 3.x.x the wifi will not work
As i check in this thread
http://forum.xda-developers.com/show...5#post51536075
i found that there are 3 nandroid versions which have x.xx.709.x as my phone
the highest nandroid for my HTC M8 is 2.22.709.4 not 3.x.x
so how can i increase my HTC FW to 3.x.x, :confused:
some friend suggest that i need to flash the nandroid , then flash stock recovery and update OTA to increase FW, but another one said that because my HTC is S-off and super CID, i only can flash all 3 nandroid version from lowest to highest and cannot OTA