The load times for genesis in DSON has improved in the latest versions of the DSON importer. Still a lot slower as native poser figures, but acceptable. (15 secs for G2F with just the base morphs vs 10 seconds for a fully loaded V4). If you add morphs (genesis with a few morph packs and genX) load time will increase to 55 seconds.

There is another (old) problem with multiple figures however. You can load 4 G2F's without the load time significantly increasing. If however you then load a 4 items clothing set to each of them, performance for the 1st 2 sets is a few seconds, 3rd one is getting slower and the 4th set takes 3-4 minutes. And worse the performance in Poser is now gone down to almost complete unresponsiveness. You can't do anything anymore such as twisting a head - the cursor keeps spinning and never comes back. In the end you have to kill poser. This is with SubD levels at 1,0 and -1.  This is what is preventing me from using genesis on a regular basis

I can easily have 10 fully clothed, haired and morphed V4's in a scene without any serious slow down so it is not the number of figures or size which is the problem

I am using the latest DSON importer, latest Poser version with SR3.2, fast video card and fast machine