Stay on 3.20, you can load PS1/PSP isos, aside from PSP emulators and the withelist trick works too.
The PS TV can be updated to 3.60 offline using a USB memory anyways, so you can stay in 3.20, download the update now and you will always have the option to upgrade to 3.60 if something from HENkaku insterests you more in the future.