I own a Pictor preamplifier (equipped with the optional DC filter), which I upgraded from the Inspiration 1.0 Pre. This upgrade resulted in significant improvements in transparency, resolution, and overall refinement.
Even when initially paired with an Inspiration Stereo amplifier, the Pictor clearly demonstrated itself as a more sophisticated product compared to the Inspiration Pre 1.0. I later upgraded the Inspiration Stereo amplifier to the matching Taurus Stereo model. While this upgrade also brought noticeable improvements, they weren't as dramatic as those experienced when upgrading from the Inspiration Pre to the Pictor preamplifier. I haven't had the opportunity to test the Virgo preamplifier in my own system (only in a dealer's setup), but I understood that the Revelation series represents the optimal value proposition within the Constellation Audio range.
I would recommend considering the Pictor, and especially the Virgo, over the Inspiration 2 preamplifier, particularly if they can be found at comparable or lower prices than the Inspiration 2 series.