Reply to Producers: Virtual Instrument Suggestions?

I can never remember the difference between VST and VSTi, but I'm looking for suggestions for virtual instruments. I guess specifically I'm looking for ones that can produce decent Electro sounds, but I'm open to any suggestions; I don't strictly produce electro. I suppose I would try making other types of music if I had a wider range of sound capability.

One that I've used in the past and really liked is reFX's Vanguard



Just trying to expand the potential of my production, I guess.