It's a personal choice I guess. I like to keep my J Series SIP and 9600 H323 firmware up to date.
If you're using embedded file management on the SD Card which it sounds like you are, you need to get the firmware files from the ZIP file you download into the SD card's 'primary' folder. The file J100Supgrade.txt tells the phone which firmware to grab and install.
-Extract all files from the J series firmware ZIP folder
-Input your SD card into your PC. Be extremely carful not to format or move anything around.
-Copy the files from the firmware ZIP extraction directly into the 'Primary' folder on the SD Card. Windows will prompt you to override any files such as languages, etc.
-Eject the SD card properly in Windows and put it back into your IP Office
-Reboot a J179 phone to test it out.
I've been running the newer 4.0.10.2 firmware since it released and haven't noticed any major issues.
Thanks, Tim
Adelaide, Australia