There is nothing "morally grey" here. You are buying an amp that performs better than majority of amplifiers out there regardless of price. the substitutes are peformant and precisely what I tested that is resulting in folks buying it. The op-amp is socketed so go ahead and get genuine one if you like. On the inductor, I am not losing sleep over that.
Let's not find a reason to complain about everything I review here. There are plenty of products that screw their customers by delivering atrocious performance and charge a ton of money to boot. That is where you want to direct your complaints, not at a $100 amp that produces so much clean power.