What soft-synths get the most use from you guys?
 
TAL Noisemaker is my goto when I need to build my own sounds from scratch or I want a lead or solid bass (and don't want convoluted interfaces or lots of options). It's probably my favorite all-around synth, and has been for about half a year.
I definitely pin it on Z3ta+ for good general presets (which replaced Superwave P8, another of my #1 favorites), though I don't tweak sounds a lot inside.
Finally I probably use CW TTS-1 the third most when I want pretty good sounding GM (and I'm willing to do just a little work to make them fit).
 
I'm just curious- I'm not looking to expand my library (as I had to purge it late last year), but I'm interested as I have a lot of soft synths I haven't gotten rid of but which DON'T get the bulk of my use (or any at all).

I suppose it all depends on what sounds you're after as each has its strengths.
I generally favour Camel Audio's Alchemy as my first choice. I do have a lot of content for it and, it's a very Phat sounding beast of a synth.....very inspirational.
I also like Z3ta+ a lot........and now, I'm starting to enjoy Synthmaster as well.
Korg's Legacy M1 is also very useful for me as well as Rapture.
There's just so many synths with NI's Komplete, so I don't even know where to start (Reaktor will keep you busy for at least 1 lifetime)........installing K9 as we speak.
 
Sometimes, I fire up a particular synth for a song I'm working on and then get completely distracted with that synth......forgetting my initial plan. 
 
 

Of all my synths, my goto is the Arturia Minimoog V Original that they gave away for free a couple years ago!

My go to synth has got to be Zebra 2 it is sounds wonderful! is hugely flexible and has lots of free and commercial patches available.
 
I have tested most of them over the last few months and found feedback from the guys here very helpful especially bits run down in recent months. 
 
I have Z3ta 2 but am not a huge fan (bit gritty) Rapture is nice and I own all the NI Komplete ones which are good and get some use .
 
I would like Synthmaster which is on the to buy list as it was also very broad in its options and sounds. 
 
But overall Zebra wins on most fronts sounds, CPU usage, teaching resources, seems to be able to cover nearly all desirable synth sounds.
 
 

Limiting to synths, as opposed to Samplers and rompliers.
 
G-Force Minimonsta is my favorite and I am having a hoot with my recently acquired XILS4.
 
The main runners up are Korg MonoPoly, Arturia Modular V, and Pentagon. For more modern sounds Z3ta takes a lot of beating.

Hardware:  Ensoniq ESQ-1, Roland D-550 (D-50 rack), Yamaha Motif 6, Yamaha MOFX8
 
Software:  Korg M1 legacy, Korg Wavestation legacy, Spectrasonics Omnisphere, Camel Audio Alchemy, Rob Papen Blue II
 
I have a bunch more hardware and software synth but those are my go to for sounds.
 
I like ROMplers.

Alchemy.  Rapture.  Z3TA.  DimPro.  Kontakt.  I've got a bunch of others but those are the soft synths I just everyday.  Even pros should stick w/ less choice until you figure out how to use a synth (or soft synth) best.
 
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I dearly love Lush-101.  Not a lot of third party sounds available, but the ones that are available are wonderfully musical.
 
Alchemy I love just for the engineering brilliance, even though most sounds tend to be a bit too "sound-scape-y" for my purposes.  Also, it's got the best documentation of any synth ever.
 
Synthmaster has a *ton* of add-on sounds that are great.  None of the libraries are overly expensive, so you can painlessly build your collection over time.  Synthmaster is probably the best all-around value going right now, bang-for-the-buck-wise.
 
Zebra 2 is totally wonderful, and there is quite a wide selection of third party content to purchase.  DIVA is incredible sounding - it doesn't have many of the usual soft-synth bells and whistles but it sounds very convincingly like the real hardware thing.
 
I just watched a Groove 3 tutorial series on NI's Massive.  I'm more than a little intrigued to dig into that one far more that I've done to date.

Omnisphere.

If you mean actual synths then Synthmaster is what I used the most. If you mean general VI/softsynth then Kontakt.