It's funny because I'm a vocalist person, not a guitarist person. Mostly because I personally cannot hear individuality in guitarists. I don't know why. I hear it sometimes, but usually, I can't find the nuances that everyone else can. Of course I can obviously tell vocalists apart because they all have totally different tones/phrasing/styles/etc. But it's difficult for me to notice the same things in guitar playing.
Adrian is one of the only exceptions. To my ears, he, Slash, Ritchie Blackmore, Randy Rhoads, Buckethead, and Yngwie Malmsteen are extremely distinctive. I can tell them in any song (not to say they're the only guitarists I like, but they're the only guitarists I can listen to and then say, "Oh. That's so-and-so on the guitar."). And they're some of the only guitarists who can distract me from the vocalist. Adrian is the star when I listen to Paschendale and Stranger in a Strange Land. His solos are so soulful to my ears.
I'm not taking anything away from Dave. I probably just don't pick up on him because I don't have the ear for him. There are times when he takes the spotlight, too (The Thin Line Between Love and Hate comes to mind, and I adore his Phantom solo), but it's just not quite like Adrian. Dave's great, but to me, Adrian's the special one.
I don't know who the most technically skilled one is between the two of them because I don't think there is any reliable way to measure that, so I won't argue that. But saying Adrian is thin, mechanical, and "not special" is laughable to me.
Just thought I'd share. I don't usually say much about guitarists, but Adrian is one of the only people I would defend like this. In fact, before Adrian, I didn't even care about guitarists at all.