Should I update my manufactures power cords?

Those amps will benefit from upgraded power cords

Also try the amps plugged directly into wall and not into power conditioner. I had AQ Thunder and upgraded to the Hurricane. The improvement was not subtle. However, in the end, I sold the Hurricane cords. They made my system sound a bit too syrupy and dark. Home audition is a must.

Being a pedant can’t be healthy.

Morning dose of entertainment - nothing beats audiogon. 
We have a multi thousand dollar isolation device that will make more difference than power delivery and we have a McIntosh amps aren’t good enough and I can make them better with a cap upgrade recommendation. 
 

The peanut gallery has spoken. 

Yeah when the honeymoon is over you realize you f-ed up and you actually don’t like the change, will never recoup your investment and no one wants your amps because it’s impossible to tell what they sound like compared to original and the warranty is void. I had done this way back when on an amp I really liked in its stock form and learned my lesson.

@bigkidz I’ll take you up on it some day may be after the holidays. I’ll stop by if it’s not too far of a drive from northeast jersey. 

And you as well @bigkidz 

The amplifier power cords are going to have more impact than the cord on the streamer in my experience. Do the power cord upgrade on the streamer last.
I would suggest getting the best possible power cables you can afford for the amps even if it means using stock cords on the streamer and preamp. Second upgrade would be the preamp power cord. The very last thing you’ll want to do, as icing on the cake, is to upgrade your Ethernet cable. If you’re using basic cheap Ethernet cable, an excellent makeshift improvement would be something like a Linkup cable from amazon.