Switch from AB to D

I have a Onkyo TX NR 3007 that eats up electricity because of 4 amps inside. I would like to switch to the Vidar class D from Schitt's. I really like what I've read about it and the reviews. I am handicapped and can't get out to listen to any class D units in my area so I'm going to depend on some people here give me a good idea where I'd be going from class A B to class D what's my sound. I will be using the Vidar with a Audio Experience Symphony preamp with three matching Telefunken tubes that have been in there since I bought it and it's serviced me well along with an Audio Experience Concerto Plus phono preamp. I have an older Soto Sapphire turntable with a clear audio virtuoso cartridge wooden body that has been rebuilt by the soundsmith what a great sound. Oh by the way I have an Oppo 103 Player for my digital along with PSB image five speakers which I got for a great deal of many years ago and they still sound good with my system.
So the bottom line here ladies and gentlemen what am I going to experience putting a Class D amp with a hundred watts per Channel in place of my Onkyo with 140 watts per Channel at class A B power?
Thank you much
Ron in Highland Michigan