I use several devices rather than a single integrated unit:
Frontier Tranzport - just transport and track controls, but has an LED screen that tells you what track and time that SONAR is on. It's a wireless unit and I can take it anywhere in the studio for punch in work or just bulk recording
Akai MPD18 - If you apply the popular mod from MPCStuff.com, this is the best velocity-sensitive pad set that I have found. A little fiddly to program, but with 3 banks of 16 layouts, you can store 48 separate layouts. I use Bank A for Addictive Drums and bank B for the General MIDI layout. It also has a single fader which is setup for master volume on SONAR for those moments when something happens to be real loud.
Akai APC20 - a recent addition gives my faders with 4 different setups (for mixer, effects, etc...) that are button selected and an array of launch pads for Ableton. Somewhat crude transport controls but functional.
I also use hotkeys on a wireless computer keyboard for a variety of things. These are all compact and fit easily on a desktop under a dual monitor layout (on Ergotron arms to keep the desktop clear for controllers. I prefer the versatility of multiple small (and cheap) control surfaces rather than the uber-integrated systems...