I have calculated my yearly use circa 1500 hours, (probably more than most) If an amp pulls 8/900 watts from the wall thats at least 6 or 700 quids worth of electricity. Per year, (7,000 -8500 pounds) over ten years... Plus the unwanted heat in summer.
That is why I bought class D monoblocks which draw a fraction of that, 50 / 80 / 120 watts tottal depending on loudness.
Your AXA tech is GREAT for lower power but you should move your bigger amps into Class D.