Timo
LOL - Ive managed to tame roomworks sometimes and have found it useful - and then sticking really brutal compression after it - but I have to agree on your general statement. I cant use it on its own.
On the dynamics - yes - it does pump easily - but it leaves everything really plastic I think. I do sometimes use it for squashing reverb laden sounds until I find something better - TBH I just dont like the end result - it has the dynamic control Im after but somethiung gets lost in translation thats Ive never been able to put my finger on.
On the multi-band dynamics - the presets I think are truly horrible - no amount of tweaking gets rid of that nasty plasticy processed sound.
Your use of it is perhaps appropriate if you want instant FM squash

I wouldnt run anything of my own through it - just hate the damn thing too much
I use a behringer DSP1420P for when I want an instant processed sound for monitoring when I'm recording. Useful for pumping out a lively sound when your recording and want to hear bit of a pumped up dance floor sound.