I've now been experimenting for over a week having loaded all three
environments - really just to find out what programs were in each.
Loading the meta packages on 'edgy' - i found it more than a bit edgy.

I found i had a fair bit of confliction - allegedly one is supposed to
chose the environment at login. Sometimes Ubuntu standard would load and
KDE splash screen tended to come on the screen at startup and shutdown.

It would seem that one should choose one of the three environments and
then add on other programs. e.g. if one doesn't like Synaptic, add
Adept. Is this MIX & MATCH what is in fact intended - i don't know? It
seems to me that they put more thought into Gnome (in terms of smooth
working and bug free) than the other two. I just wanted to have a rather
more windows environment than Gnome offers, but KDE offers that but with
a penalty of lots of games, much slower and similar apps like Koffice
suite (poor compared with OpenOffice) - i.e. rather bloated. I still
can't get windoze style desktop icons.

So "missing out" - from what i can work out the standard Ubuntu is best
and add on the one or two KDE programs you want.