I think I really made a good move when I upgraded from the unpowered Kemper to the powered version.
Playing through my EVM12L-equipped Thiele cabinet, it just seems that the sound is so present and full. Definitely an in-the-room sound, though a bit more high definition than a traditional amp. That still comes across beautifully and hangs well with just about any 4x12 I can think of (given that it's a 200-watt speaker).
Comparing the sound to my studio monitors, I feel that FRFR seems to add a certain brittleness to the profiles given that it reproduces all frequencies. Or maybe brittleness is the wrong word: it just seems that the high frequencies seem to add a harshness to the tone.
A guitar speaker on the other hand only reproduces a certain range of frequencies before sharply dropping off in the high end and low end. That makes it sound remarkably warm and full-bodied.
It really makes me have high hopes for the Kemper Kabinet. I would really love to be able to see what a full-range guitar-oriented speaker would sound like.
The EVM12L is great, if only a bit more limiting in terms of profile differentiation since it adds its own colour. I can definitely say that I wouldn't mind sticking with it if the Kabinet turns out to be extremely expensive.
EDIT: Here's a video.