Will the WoS plug-in sound the same as the Torpedo Studio, Live or C.A.B.?

The way the WoS plug-in processes the signal is identical to what the Torpedo hardware does, so in terms of speaker emulation technology what you get is exactly the same. 

The only differences between our products are listed here and include, for instance, the Overload feature, or the number of cabinets you can emulate.

What you want to consider is the interface. The Torpedo hardware embeds very high-quality converters designed to bring you state-of-the-art analog-to-digital conversion. The plug-in, on the other hand, will be dependent on what soundcard you are using.