If I wasn’t doing active crossovers, I would love a setup like this. But amping per driver, it makes something like your amps cost prohibitive. Then again, if you are doing only 2-way bookshelves and a single sub, this would rock! Low distortion on the highs, fast responsive bass, just tackling whatever you throw at it. If you add two more channels, you could do 3-ways with a sub. And then if you ever change your setup, that would still support 7 of a 7.1 channel setup.
Either way, awesome working build!
What is your opinion on driving with a SMPS instead? KISS Analog had a good video awhile back looking at linear vs smps and found a bit less noise with the SMPS, if designed correctly (also may require a couple tweaks if your smps is putting out too much from the switching frequency, but if you pick the right SMPS, should not have an issue).