Sustain wasn't a bad product for the time, but now, with Forma and POST CYCLE and even the availability of anti e's, there's no need for it.
With what's available today, I believe Clomid or nolva isn't necessary,but even if you don't have a a bad aversion to it, using HCGen on cycle, and BRIDGE post PCT, you'll do a lot better and recover faster and more fully.