Ok, so I spent an hour, or so, playing the Holcomb yesterday. Admittedly, I am not a drop/down-tuned kinda guy. I'll go there, but not often. This guitar does that in spades, and everything else wonderfully. I really like almost everything about it. The pickups are very percussive and have great clarity. Punch ya in the gut with a load of gain, and lull ya to sleep with pristine cleans. It really covers a lot of ground. There is noticeable volume drop when split though. Nothing you can't work around, but it's apparent.
I actually recorded a bunch of stuff playing through the different pick up combos. But, being the doofus that I am, I was sitting about a foot away from the cell phone. Too much of me hitting the strings to post. Maybe I'll try again tomorrow.
As for the 25.5" scale, it's not my favorite, but it's not that big of a change. I can see someone that never goes there having an issue. With time, that can be a non-issue. I LOVE the black satin neck and ebony board. It feels smooth and yummy! I will say that the specs say that the frets are "Standard PRS Fret Wire", but they seem a little on the big side to me. Don't know why, but that's just my opinion. YMMV. The ebony board is looks slick, and feels the same way. Big fan of ebony boards.
I also really like the string through bridge. I find it comfortable for my picking hand position with no sharp edges. Very smooth.
The 20" radius is obviously built for the shredder. It's a little more challenging for chords if you're coming from a 10" or smaller radius, and haven't spent much time with something flatter. You'll feel it in your forearm, that's for sure. Again, if you've spent time jumping back and forth from a small radius to a bigger one, you'll be ok. Otherwise, it may take some getting used to.
My only qualm would be the wide thin neck. It feels really chunky with the 20" radius. At least it does to me. Personally, I would prefer something with a little less neck depth, or a different shape profile (C, D, soft V, V, etc). But that's just my personal preference. To compare; I have a JPX that has the same width measurements as the Holcomb, but the depth is 1/16" less. That feels better in my hand with a flatter radius. There also is a difference in profile. YMMV.
All things considered, this is a killer axe. What you get for the money is beyond ridiculous. I would recommend it to anyone looking for a great instrument.