Guys-

I'm a little technically challenged, you might say...

So-

This is the box mixer I've used with great results: http://www.music123.com/Behringer-PMH2000-Europower-Powered-Mixer-631240-i1153483.Music123

This is a powered mixer I'm considering: http://www.music123.com/Behringer-PMH1000-EUROPOWER-Powered-Mixer-631252-i1153492.Music123

Can someone decipher all the tech talk and in plain English describe to me the main differences between the two?

I've seen several on line reviews indicating that the pmh1000 is not nearly powerful enough, even for mid sized rooms.

It looks like, spec wise and power wise, maybe this model is closer to what I've been using (pmx2000 is the one I've been using, happily)
http://www.music123.com/Behringer-EUROPOWER-PMP1000-Powered-Mixer-630149-i1323949.Music123

Help!