I've not heard the V5, but the CDM is a wonderful amp. My ALO addiction means I own a new Rx, a CDM and will probably get a V5, just because...
The CDM drives my HD800s beautifully. I have the output of my Hugo turned down (light blue) and the volume control is only around a third on high gain. Dare I say it, the sound is more euphonic and musical than my Liquid Carbon, though with a touch less detail. Since I received the CDM, I've really not used the LC that much. I'm not sure about planar magnetics that need power (more importantly, current) but on high impedance headphones, run balanced, the CDM is utterly beautiful.
Even when the V5 arrives, the CDM will always have a place simply connected to my macbook pro as the most compact desktop setup I can think of that makes the HD800s sing.
The Rx is equally magical. Whatever I connect it to (Hugo, Mojo, Naim SuperUniti), it makes my Noble Kaiser 10 CIEMs sing. There is huge synergy here - Though the K10s do not need much power, their complex crossover needs driving with an amp that can supply the current swings that the corresponding impedance curve requires on music program.
Roll on the V5 - It will be extremely interesting to compare it to the Liquid Spark - I sense this will be the forum battle of the month once they are both available.
Again, congratulations to Ken and Vinni on a superb range of beautifully engineered products.
Cheers,
Peter.
PS
Does anyone have a spare pair of CDM Mullard 6112s they want to sell me? Pretty please (-: