I have been eyeing for Access Virus TI ever since the first time I heard about it a few years ago (yes, I'm a bit late to the game). Initially, I was just curious: as the software synth grow more and more powerful these days, what's all the fuss about a virtual analog synth? I mean, there are many other synths that can do what virus can do and more... Or is there?
Well, first thing first, the Access Virus can do almost ANYTHING you desire out of a digital synth (be it software or hardware). I said almost, because there are few niche (complex FM with more than two oscillators) or new technology (resynthesis) that the virus can't do, but for most users, what the Virus can do is much more than enough. FM, Wavetable, Granular, Dedicated Supersaw (No the same as unison, which can actually be applied on top of the supersaw), and unique formant oscillators. On top of all that, the Virus also has some superb effects: reverb, delay, chorus, 3-band eq, vocoder, distortion (more than 20 modes!), character control (you can for example add some analog warmth or add enhancement to the lead or bass sound), a punch control (how much transient do you want).
Can I get all those using some software synths? Sure, I guess. But is there ONE synth that can do it all? Maybe, but definitely not as intuitive and straightforward as the Virus. I own Omnisphere and UVI Falcon, and they are deep and can get really complex, so they should do what the Virus can do and more, but when I use those synth, I often got lost in the GUI very quickly. The Virus somehow achieved the balance between depth and user-friendliness for general users like me. I said general users, because of course the complex software synth can do some crazy stuff the Virus is incapable of doing, but will those sounds end up in my music? Well they can, but probably won't. What the Virus can do is already more than enough for me.
Also, what I just wrote about is merely about capability, not the actual sound. The sound of the Virus is just so unique and can punch through the mix without doing collateral damage to other tracks. I think all the other software synth I have can only get "close" to the actual Virus, but it's never really the same.
One last note, don't be discouraged by the fact that the developer has stopped updating the software editor (but it doesn't mean we should stop bugging them). There is a third-party librarian/editor from Aura, which can even do audio over USB for newer macOS (the official one stopped working since Catalina, the Windows version however, is FINE).