The selection will also depend on the fact if i ever programmed any sounds with a specific synth or if i only used the presets. Even if i got a bunch of soundsets for several synths i found myself to prefer using my own presets.
A difference are soundsets for e.g. NI FM8 as so far i'm not really good with programming pure FM synths (which will hopefully change and i already have a few own results).
To be honest i have only used Kontakt 4 and FM8 from Komplete 6 most of the time and Massive, Absynth, Reaktor only very few to almost never (which was different when i got the package). Maybe i'll rediscover those other synths in the future but at the mont i don't really need them.
Besides all that i prefer also having a small amount of hardware synths.
In fact if i am really honest those 4 hardware synths (Motif ES 7 with 512 MB RAM, Wavestation EX ith RAM card, Blofeld desktop with SL expansion, Moog Slim Phatty) would be more than enough for doing music but that's another story.
Ingo
