Zen vs. SOZen

I'm considering building a Zen amp and pre-amp, and wondered what everyone thought of the origonal Zen and bride vs. the Son of Zen and it's bride? Which pair sounds better together? My only sources right now are a DVD and TV. Would building a passive pre-amp (instead of one of the brides) be a mistake? How do they compare to the Aleph 3 price and sound wise? What do I need to watch when trying to match them up with speakers? Thanks for your help.
There have been many threads on the subject of comparisons between Pass Labs amps and preamps, I have initiated several myself. If you look back through the pages you will find a lot more about the ZEN series as there seems to be a bit of a lull in interest at present on this site.

I have to date built a 10 watt ZEN (original not revisited) and a ZEN/SOZ hybrid, basically a SOZ without split rails to increase efficiency (this one was only 4 watts). The difference in sound of the 2 is apparent but I still cannot pick a clear winner. I think this depends on your tastes and what speakers etc. you are using. Note that the SOZ is hugely inefficient and requires more than twice the heatsinking/power supply of an equivalently powered ZEN.

I have not built or heard either of the preamps but I believe popular opinion dictates that the BOSOZ is supperior (even Nelson Pass believes so).

Hope this helps