OP-X

Sound: It's all about the sound for me, and this synth NAILS the late 70s SEM filter sound. As a result, not only is it a spot-on OB-X clone, it can sound just like a Jupiter 8 and Prophet 5. Warm and lush to cold and digital, this synth sings in all the ranges.

Features: In many ways it's the VSTi synth I've always wanted; fat, analog, sweet filter, with great modulation features. It also has a killer FM/ringmod implementation that goes beyond the original OB's capabilities by allowing one or both of the oscillators to be a sine wave.

Download the demo, try it. You'll be hooked.

UI: Very authentic. Some of the controls are a little on the small side, and some things won't be obvious until you read the manual.

Presets: wonderful banks with emulations from other synths, and the Famous bank is hilarious- I could name almost every song each patch was used in.

Customer support: lots of updates, fast e-mail response. Very good.

Value for money: this thing is a bargain at $99, plain and simple.

Stability: Rock solid. CPU use is a little higher than most, but very similar to, say, the TAL Uno-60. Totally worth it though.

When I first heard this vsti, I had to buy it! I use it for leads using my Akai EWI4000s and it delivers! It reads midi controls great live and what strikes me the most is the portamento.
If you're looking for a realistic, sweet, FAT analog vsti, this is the most realistic, sweetest, FATTEST one I've ever found! When they said Oberheim OB-X clone, they weren't kidding!

I'm not the one to design sounds, even though it's easy enough with the GUI, I just use the presets given and they give 400 of them for your use! I particularly enjoy the leads provided because of my particular use and they are colorful. I enjoy the variety.

It has an attractive GUI that mimicks the Oberheim OB-X pretty well, although using it's keyboard with the mouse is a little difficult trying to hit the black notes.
The one real gripe I do have about it, however, is that notes hang in Sonar when stopping and editing midi and you restart the song until it hits the particular note(s) that's hanging. Other than that, it tracks really well!

I don't know why it took me so long to find out about this product just after I already spent the money on Minimonsta, but when I heard the sounds coming from OP-X I had to throw down the cash immediately. This synth is FANTASTIC. Its the near perfect 80's rock synth, but it fits many other styles as well. The SEM filter emulation is so spot on its scary. Think Rush's "Tom Sawyer". This is one of the fattest VSTi synths I have ever played, mostly due to teh way they detuned each oscilator voice individually, and in a way that is authentic to the original.

I also recently picked up MiniMonsta and IMPOscar which I also love for different reasons but I have to say the OP-X has won my heart over even both of those two well respected synths. The lead sounds are thick and ballsy. The sweeps are great. Lots of great brassy sounds.

I have never actually played an Oberheim synth, but I hear from other people who have, that this emulation is very very good. I sort of don't care whether its authentic. It sounds fat and ballsy and that's all I care about.