Redspecial's obviously referring to demos of the profiles... at least, that's how it looks to me.
Mate, as Gianfranco asked earlier, and as I've been dying to ask too, have you tried decent headphones as a means of checking the author-sense-titty of profiles that're sounding crap in the room?
Another thing, and it may be invalid if you've used the room for real amps and been happy with the sound, but does it (the room) lack treatment? Are there flutter echoes bouncing about? The only wall I see in the video looks like a prime candidate... for accentuating and possibly phase-cancelling pick noise, which is a "symptom" you've specifically mentioned.
In addition to this, if this is what's happening, the "colour" of the room's effect on everything you play will contribute to a sameness across the various profiles you use, and the louder you play, the more affected the Kemper's sounds will be.
With any luck this'll help. There's definitely nothing wrong with what the Kemper's capable of; nothing else comes close IMHO. Actually, I'll amend that to "remotely close".