The comparison, part for part, is no different than any other spring driven pedal, really. The main thing for me, instantly noticeable, is the physical comfort. That allowed me to play more fluidly for much longer periods of time with no stress on joints.
Some years back I was sitting in front of the tv watching a drum video. I set up my dble pedal (Yamaha), beaters downward, and I had my practice pad. I placed the pedal centered in front of me, like I naturally sit, so the beaters were off to my right. Don't know why. I just did. I noticed an instant relief on my back and hips and knees. I was stunned. I had seen pictures of guys who place their bass drum off to the right a little to encompass that configuration. I tried it but, the visual effected my balance and everything felt off.
I didn't know bi-lateral pedals existed. Right around that time I saw a thread on a forum about the Sleishman and the OFF-SET came up as well. I emailed Charles, and immediately ordered one. I married to it right off. It not only has nice features for adjustments but, having the kick centered in front of me felt empowering somehow. The feel of the sound is centered and seems to enable a more balanced approach back and forth, pedal to pedal, and the design ensures the feel is exactly the same between the two. The cam adjustment is really nice. Like Yamahas it has the spanner bar below the axle, which I believe creates a more stable feel. The board is wide and the unit is built like a tank. Like I mentioned above the double set of springs really makes a difference, too. It's a world class pedal. After various DW, Pearl, Tama and Yamaha (my previous favorite) dbles that pedal became my favorite. I used it until getting the Drumnetics, and I still have it and use it right now, while I wait for the Drumnetics slave.
I own the Drumnetics double and love it but, I'm not going back to the traditional bass drum placement. I don't mind placing my edrum kick off to the right and using the Drumnetics for that. For now, though I'll use the Drumnetics along with the OFF-SET center section.
I have never tried the others. The Sonor is just ridiculously priced. The Sleishman ... you either like the pedal spread or you are stuck, like the Malleus. The OFF-SET has a great price. No brainer for me.