i would have to say that picking a favorite from among so many great sounds is a difficult task.  Dimension Pro is the first virtual instrument that truly inspired me to build a computer capable of harnessing this amazing sound shaping instrument!  The market is flooded with virtual instruments these days, but this was my first love
 
If you like ambient sounds it is easy to get stuck in the "Dimensions" category.  And there is plenty more in the Pads.
 
The plucked strings patches are very interesting, as well as the orchestral samples.
 
But I must say that the DSF -Vol10 - Hollywood SFX is the most fun to play around with! 

I agree. Still a shockingly good synth. I picked up the pack with all the different Proteus expansions, and it's like a history lesson from the last 30 years of music.

I used to have sonar crash and once i got solid state drives, problem gone.
 
Sonar does not like it when i link to a project in onedrive, the constant updating causes unnecessary processor bandwidth problems.
 
I would like to see a whole expansion on brass in DP.
 
Dimension's brass is really good but not extensive enough.
 
Brass can take on many funky motifs...  

I also like a lot of the solo sound lead instruments in DP, they have unique dance and techno textures.