I don’t use software anymore ( until now ) but I like the UHE plugins - ass well for synth’s as for FX . ( great sound )
The best Soft-Synth for me is the Z+ ( not from EHU ).
There’s a BIG MOOG emulation I liked ( forgot the brand ) .
But I prefer Synths who don’t try to emulate but do there own thing ( and sound good). VANGUARD sound great and it’s for free.
Go for the Z+ if youneed good sound - easy programming - and originality.
For me -nothing beats hardware.