Hi Tubedude,
The TGX-50, IMHO, is the best Kick drum mic around.
It provides a much more Natural sound than any of the other "economical" Kick Mic's available.
I bought AKG D112's, not because I prefereed them, but at the time I was running sound, and it was expected....it was the standard, and guys would start whining if you didn't have that "football kinda mic" since their friend so-and-so told them it was the best kick drum mic that was ever made.
My Opinion of the D-112 is that you don't even NEED a freaking Bassdrum. Just set the Kick pedal up to so that you can hit the mic with it (It's Joke don't try this at home kids....hey you never know, some kid might think I'm serious

), because it's going to have what I call "Thick with click" no matter what you do. (For Metal that's fine, but what if you're trying to do something where you don't want the kick drum to sound like Pantera?)
Whaty if you want a Diary of a Madman type of kick sound in contrast to the Pantera sound? (My ideal drumsound being the sound that Lee Kerslake had on
Diary of a Madman, even though most people still think that Tommy Aldridge played on that release. Max Norman ROCKS!!! He's still my favorite producer.)
The TGX-50 goes for around $180-$220 depending upon where you look, and what you can find on sale.
As for the CAD, I can't tell you anything about. Sorry
Of course my brother's band recorded in a studio in Nashville, and they had a box with several CAD condensers (And I was thinking about buying one at the time) and they told my brother "CAD = SHIT".
So, ever since then, I have steered totally clear of them.
Tim