My Anthem M1 mono blocks are rack width, fairly deep and only about 1.75 inches tall. They weight around 25 pounds each, so 50 pounds for the two mono's. Since I too love the look of heavy amps and fancy handles; I machined a pair of fancy billet aluminum rack handles which are about 5 or so inches tall and perfectly fit to the heavy 1/2 inch thick front panels of the M1's when the stock 'winged' handles are removed. The two amps mount into holes machined precisely to match the OEM threaded holes in the panel from the sides at the top and bottom of the rack handles. So what I have is one amp suspended on top of the other amp with a 2 inch spacing between them for air circulation, vs simply stacking them directly on top of the other. The amps as so well built that the machine bolts going through the handles into the sides of the amp front panels is all that is needed to fully support one amp free floating over the other.
I did put a rubber 'doughnut' at the back of the amps between them just for additional support for a just in case moment. But from the front or side view, all you can see is these two gorgeous amps floating behind the rack handles with the heat sinks on the sides... It looks fabulous. Next I plan on doing something similar with my stock Preamp. This is all useless superfluous eye candy, it does nothing for the performance or sound.... but probably the same can be said for 150 pound Class AB amps with super thick case work. I am lucky that I have the equipment to make this stuff myself.
the two amps stacked with the large rack handles give the pair the look of a large Class A/AB amp, but it's still my wonderful Class D's with all of their efficiency :) :) I have the best of both worlds.