HI, personally I prefer the nac102 and nap180 combination which is a very good solution. The new 5 series is exactly like the slimline so it's 58mm height and the height of the other devices is 76mm.
I heard last week the cd5 with the nait5 and after the same cd5 with the nait3r on an intro pair of loudspeakers and frankly... these devices works so good together. I prefer the new cd5 with the nait5 than the cd3.5 with the nait3r but these sounds very well indeed ! :-)
Maybe I want to try a nac112 with two nap150 in a passive bi-amplification configuration... I don't know.
If you choose the nac102 and nap180 amp line, I recommend to put the cdx with it ! god ! this is music :-)
...then upgrade for a hi-cap (or super cap) to power the nac102 and cdx.
frankly, I'm pretty sure that a system built on a nac102/nap180, hicap and cdx is a great system with a great value. And of course and great sound !!!
cheers, ERIC