KANKER  Zebra is simply the finest synth plug in on the market, in my opinion. With it's extremely fat filters, Zebra produces some of the warmest sounding synth patches you've ever wanted to hear. I've been using this thing since v1.0, and I haven't felt the need to buy another synth plug since - it's just that good, and with v1.5 it's getting plain ridiculous.   
(Version 1.5)

AARON CLARK  The Zebra is awesome, it puts most hardware synths to shame.

Zebra can do the great classic sounds with ease and it is just as well suited for modern music needs!

Zebra also gets along with other synths and is a great tool to have.  
(Version 1.5)

FILARION  this is one mean synthesizer. warm oscillators, modular signal flow, sweet gui. highly recommended for both musicians and sound designers.  
(Version 1.5)

HYERSTAY  An amazingly powerful and easy-to use synthesizer with massive routing and control possibilities. If you buy only one synth, this should be the one.  
(Version 1.5)