HI,
I've owned a NAD 541i, which was really nice for the money.
At the moment, I believe they (NAD & Cambridge) are both made in China, and use decent parts.
I think they use different Dacs (the NAD uses burr brown) and the Cambridge uses either wolfson or crystal (again check on that, these things change). I think they are equivalent, and I would listen to them both in my system and then decide, based on what sounded better to me.
But they are both very good value for the money.
-akhilesh