Lol rest assured the HD will be getting updates past 4.1.1....
If you are able to unlock the bootloader (xt925 or dev edition xt926) then you really have very little to worry about. You can always fastboot restore the device if something goes wrong. Or, even easier just flash a custom recovery, make a backup of stock and you can simply flash/restore back to it if there is ever a problem.
Along with that, rooting with an unlocked BL is simple. Use a custom recovery and flash the su.zip.
My bootloader is unlocked and I've been on every ROM we have available, both through safestrap and TWRP. Its a lot of fun.
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