I have a quad cdp2 and I think it's a fine transport..the260d is little more expensive..just a tad! Hardly surprising that its better? My xt se is a better transport too..not sure it's ' much ' better? I would recommend the quad as a transport without hesitation as its a dac and pre amp too..unless someone has reference speakers and similar amp, cables etc..then a 260d or xt se would sound very good..however if they haven't..then quad cdp2 fits in nicely..want to go old school? Mission pcm 7000 is a fab transport and excellent cd player in its own right..as its dac is awesome..
The Quad is very good, I enjoyed it for many years. It's fixed outputs were much better when used with a nice preamp as compared to it's variable output which wasn't great.
The Moon is significantly better to my ears, and I don't hear differences that easily.
I have a decent system, not sure it would be classified anywhere near 'reference'