The Upgrade Company gives a warranty for its work, ask them
I had the Upgrade Company modify a $1000.00 CD player. The work was very poor, and they would not give a refund, not even a partial refund. Their "Satisfaction Guarantee" turned out for me, to be an advertisement only. Their claims of "State of the Art" is simply not genuine, because they don't design and manufacture Audio art.
This is not to say they cannot improve the sound of equipment by modification, and better parts. But from my experience and what I have heard from a few others, I would not trust them or pay high prices for their services.