I'm editor of emotuned.com music / samples store platform.
Linear Samples released two new/unique Kontakt samples libraries, based on renewed 80's 4OP FM synth (Yamaha YS200) and Linear Arithmetic synthesis (Roland D-20).
The provided instruments cannot be reproduced by other hardware synths nor virtual plugins : YS200 relies on its unique reverb and fast LFO with sample&hold, not available with FM8 and others, while Roland D-20 custom patches rely on its unique sounding resonant filter (both warm and precise, a finer grain that the D-50 can't reach).
The included sounds are also very long sampled/looped (up to 20-30s per note, and up to 180 MB per instrument) and really cut through the mix, with deep bass and well captured filter sweep.
Since I use these I don't need other synth virtual plugins (that sound thinner), you can check through the demos (more on the site) :

ItemD (D-20 custom instruments except drums)
ItemD (ogg version for Firefox)

Blizzard (YS-200 custom intruments)
Blizzard (ogg version)
Jerome