Steve Deckert of Decware states that you can leave the Mini Torii SE on for days:
"In addition to it's small size (8-1/2 x 11 inches) it also runs extremely cool making it friendly on your desk top or on hot summer days. No stress involved in leaving this amp on for days at a time... it doesn't care."
Long life - all internals are way overbuilt, there's just nothing inside to fail. Expect 50 years of use out of it without problems.
I wonder which capacitors he uses in his Mini Torii SE.