I flashed my panel at the weekend from v2.1 to V4. The actual flash process was relatively easy. Though the steps afterwards caused me a bit of grief for a DIYer. Connection from wintex via my comwifi module is now very hit and miss and i can no longer use the IOS app. I ran out of time, but i think it's down to the new encryption. Texecom do advise to do a factory reset after the upgrade which i didn't do (due to time) so perhaps i'll try this later this evening.
The main reason for me upgrading was for compatibility with the new miniature contact sensors.
Well that's interesting, you would think after the update everything should run more reliably, hopefully after reset it might, but I think texecom need to work harder and provide swifter updates. I'm still considering flashing but no rush at mo.
firstly should follow manufacturers instructions, they are not there for fun.
flashing up and defaulting the panel with wireless will create its own issues, you may find that if you didn't back up the config with radio devices that you have to learn them all back on and re do commissioning mode, always wise to recomission and check devices after a flash upgrade.
my biggest concern is updates of wireless expanders takes please when new devices are added and you may find that if the wireless expanders are not uptodate that new wireless devices don't work so well.