The V-Synth GT is not a traditional ROMpler since it doesn't come with large multisamples for pianos or strings. Don't expect to use it as a all-in-one synth. Real instruments are not in that thing. But thanks to the new AP-Synthesis, solo sounds like violins or flutes are very realistic and expressive. You also have sort of a JP-8000 engine for analog modelling, a powerful vocoder and the internal sampler is great to use and edit with the touchscreen.
I love my V-Synth GT since it's so easy to program and perform. Lots of good ideas, like the MIDI Clock synch for LFOs, chorus effets, delays, arpegiator and step sequencers.It's a beautiful instrument, too. Solid and well built.
Due to polyphony consumption and mono-timbral mode only, don't even expect to use the V-Synth GT as a MIDI module for your Cubase. But if you already own a workstation and search for a good sound design tool, the GT is a good choice.