I love the Sage pres.
In the past 4 years I've used them on just about every source I can think of (they were the nicest pres in my old portable rig, so almost everything went through them at one time or another). I've used them on Strings, Amps, Room mics, Oboe, Sousaphone, Gamalon, Cimbalin, Bass Clarinet, etc etc etc. As far as having a crystal clear pre with great bottom end they're one of my favorites. But by far they've exceeded my expectations on Kick and Snare. They've beaten out everything I've put them up against, including Neves (class A's and class AB's), API 312s (both the board pres in my 1608 and in the A2D), Chandler germaniums, Avedis MA5's, and a bunch of others. And this is covering a ton of different styles. I can't speak highly enough about them.
Now for the few downsides: Yes, the phantom power switch is confusing (it looks like the on/off switch for the unit), but you'll figure it out pretty quick. They're not very high gain (55db), although you can have them modded for up to 75db by Sage. And most of the gain seems to happen in the last 5% of the knob, so if you're working at higher gain levels it can be difficult to stereo match them. Finally Sage's rack mounting options are kind of lame. I built my own
Additional upsides: For their quality they're cheap as hell! Even including the external power supply. Plus, I think that Janet and Phillip may actually be the nicest people in the industry. Just give them a call and you'll see what I'm talking about.