Sandboxie Support

I've kept up with critical updates for some time, but with XP support ending I have one rig that will not be supported.

Also, using SBIE along with AV (and some good common sense) on my main Win7 SP1 rig, I'm questioning how much any Windows updates to 7 are really needed.

I would update W7. I even did the update that was supposed to give an easier update W8. It came forced feed as usual.
With not updating, you might leave some backdoors to hackers available.
Sure with SBIE you might be better protected than most users.