OP:
I recommend SMP and LiFT as must-haves and the least expensive unit with that is the PST-8. Beyond that, the Elite 15 PF (or 20 PF) adds things like power factor correction and multiple separate power banks and switched outlets, which are great when used with a processor and extra amps. That’s what I use.
If you know you have unsteady power a unit with voltage regulation can also be considered but they are a significant extra charge as it requires a big heavy transformer. It will keep your AC voltage within a tight 7V range except in the worst of circumstances. I lived in a complex with 130 VAC (long story) and the regulator kept me between 118 and 122VAC.
Honestly if the PST-8 has the necessary outlets for you it’s an excellent choice for simple systems.