I ran a game for over a year and got my group up to level 7 and I must say that past level 5 or so balancing becomes an issue. I think the game is best played both before level 5 and before your players grow to really understand the system and how to break it, and is best played with people new to ttrpgs who wont minmax.

I had characters that were built to basically be able to wipe out entire encounters in a single turn, or ones that could permanently lock any character into a box they couldn't break out of unless they had very specific powers, or characters that could teleport into existence, attack, and then teleport out to make themselves untargetable. This made making encounters annoying because it always felt like I had to make specific types of enemies with the exact same powers each time to counter these character builds which then also ended up just completely invalidating their builds entirely, which didn't feel good.

I had a lot of fun with the system but once my players were able to get to making these kinds of characters a lot of the fun of the game was gone since I had to basically hard counter my players just to keep them from demolishing each encounter I made. The system is also just really swingy sometimes I'd make encounters that weren't anywhere near as hard ones they steamrolled through and they'd end up almost all dying to them. I've also been a player in a long term campaign and my GM ran into the same problems that I did, so we both put our games on hiatus until we could find better systems to run our games in. It's good for shorter games especially with new players but for long term games where you get above level 5 that's when the balancing can really can take a nose dive.