After a couple of months using the device, finally HTC One received the update I had been waiting for, the 4.2.2.
It took almost an hour of downloading and a further 15 minutes of updating. And finally due to the use of HTC Sense 5.0 shell, there were hardly any difference to the interphase.
The camera seemed to have an upgrade now, mainly allowing me to meter and focus from separate area. Good for my kind of photography. There was also an update to the Zoe system but I had yet to use it. Sadly, I have yet to find a way to enable the famed panoramic stitching I got on the Nexus 4.
The software seemed to be OK so far. No crashes. No incompatibility issue as yet. Will update more after a couple of days use, and we shall see of there were problems.