I love these things. I have two sets of the Mainstream + Snubway combos and use them at each end of my system—one for my front end and one for my amps. Just like it’s advertised and you’ve read about. I was skeptical and tried one, then followed that with a second set. Amazing how much “noise” is filtered out and how the combo helps to let your system breathe.
If I was just getting into this hobby and know what I know now, the two areas I’d focus on first would be room acoustics and power delivery. Get those right, or as right as possible, and you’ll be a happy camper.