What's so special about xcompmgr on suse?
 

I'm not interested in eyecandy to the extent of using xgl but I do like drop shadows as it seperates windows better and gives a nicer look overall.
Now, I have always used xcompmgr/kompmgr in the past and even though I don't have a supported video card, on most distros everything has run pretty quickly with shadows enabled, particularly on suse (10.0 and 10.1) but I've noticed more recently am unable to run shadows on any distro other than suse because it is so slow it's unusable. I don't know why it has become so slow but on suse there has never been a problem, in fact on 10.1 everything is running faster than ever.
Of the distros I'm currently using (in my sig) suse runs faster with shadows enabled than the others do without shadows enabled.
I'm wondering what it is about suse or xcompmgr/kompmgr in suse that makes it run so well.
My xorg.conf is almost identical in all the distros.
I've also tried using alien in kanotix to convert the xcompmgr used in suse 10.1 but it is still just as slow on kanotix so it doesn't seem to be xcompmgr itself.