I recently changed over to DCC and before doing so studied (and tried) several systems at exhibitions. The best for me was definitely NCE PowerCab, a good price, VERY easy to use (I knew nothing about DCC), and expandable, if neccessary.
I am very happy with my decision, and really enjoy running sound equipped locomotives - well, so far I have only done a class 37.

But a 31 and an 08 are next.