For me (and I'm not attempting to evidence this, it's just my preference) peace of mind in terms of longevity. The components and wiring/soldering joints of the originals are decades old now and have increased potential for unreliability. The craftsmanship of the rebuild really does appeal also. Plus, the cost of this amp to me once I'd sold the STA 25 I was replacing it with was £200, which didn't break the bank.
I appreciate some will prefer original and minimally serviced units, and that's of course fine. But this was my thought process. Oh, and it's as pretty as a peach. How dare you call me superficial