@mmcentyre I have the Grand Illusion Sig II - High Current power cord. Before providing my two cents, let me provide some context because too often people jump into "fanboy" or "hater" camps with primitive advice and conclusions.
First, I've had tons of power cords in my system for over 20 years...even a Vans Evers Pandora tune-able power cord...so I've seen and heard a lot.
First thing I would say is save cabling to the very last thing you should upgrade. I'm not a 100% cable denier or 100% advocate. However, many people make the mistake of trying to fix poor gear or mismatches in equipment with cabling. That will lead you to disappointment no matter what brand or how much you spend on cabling.
If you've TRULY maxed out on the equipment side, then cabling can be a worthwhile upgrade, but even then...don't get crazy with expectations.
Personally, I would start with power cords over interconnects or speaker cables. (The one exception is if you are using something like Spectral amps and need to use MIT speaker cables. Those matches can make a big difference.)
It's especially best to ignore interconnects if you are using XLRs. I haven't found much differences. If you do find a difference, it's likely due to improved connectors. IMO, that's where most of the performance gains can be heard/measured so look for cables with the very best connectors (Furutech/Bocchino/etc).
Getting back to power cords...Let's get this out of the way first...Most are overpriced and/or snake oil. The price to performance ratio is extremely poor.
Generally speaking, the better your power supply...the less a power cord will impact performance. That being said...most power supplies are not perfect and even if you reduce the inductance in the last 6 feet before entering your equipment, it can measurably reduce the total inductance and resistance including the romex in your wall. When you combine that with better connectors, it makes the case even more compelling for a power cord THEORETICALLY helping things.
Theory is different from reality though. Just because something measures better doesn't mean it will be audible (or audible in a positive manner).
In my case, the Verastarr cable was a slight upgrade sonically. Same is true for a friend of mine who bought some too. We both had max level gear already (he had full Ayon gear and used 3 of their power cords and noticed the biggest improvement). I had similar notes of improvement in more refined/articulate bass performance.
On the flip side, we loaned the cables to a friend with a more modest system and different type of amp (SET), and he found his performance actually diminished in the bass.
Will it improve your system? Is it worth the money? Unfortunately, I can't give you a categoric answer. I can say I haven't returned or sold mine...neither has my friend.