dont know about the machine bro, but if you want to develop power, just try this drill three times per week:
1) stand with your nose touching a heavy bag.
2) assume the karate horse stance.
3) with your left hand push the bag away.
4) let go.
5) with your right hand punch the bag. then left and keep alternating.
6) keep the bag at a 45 degree angle.
if the bag comes down and smacks you, you lose. start again. if its too hard then dont go into the horse stance. assume a regular fighting stance. start with 30 second drills keeping the bag at a 45 degree angle. rest for a minute between drills. over time you will increase the work interval to 3 or 5 minutes and decrease the rest interval to about 30 seconds. this works for power as well as endurance. it will kill speed however. hit the bag hard and clean each time and aim for the same spot each time. if you can keep the bag at a 90 degree angle for 20 hits then that is fuckin impressive.