I agree that in my opinion the ML23 is a better amp. That said, If it were me I would get a ML23.5 instead. That amp is very, very nice. it has different input circuitry from the 23 and I've owned two and still have one. believe it was the last that actually has Mark Levinson (the person) design associated with it before he sold the company.
I've compared it with amps today and I beats most.
just my two cents.
enjoy