As mentioned above, the big multi-channel Monolith amps are made by ATI, and ATI is all about reliability - they're built like battleships. I can't say what's going on with Amazon, but I did have a bad experience in purchasing an ultra-wide Monoprice computer monitor from Amazon. The monitor arrived with only half of the styrofoam packing material in place, and the monitor had a cracked screen. I returned it for a refund and proceeded to purchase another two directly from Monoprice - they arrived perfectly.
I think the moral, at least in my limited experience, is to purchase directly from Monoprice, NOT Amazon!