This isnt exactly true.. Ive gotten better arm workouts with my bands then at the gym somtimes.
I have bands that range from 5 to 50lbs..high quality.. Not that flimsy crap from walmart.
Depending on the stretch and how they are used the weight can even be much higher. and the tension is constant and steady ..
I use to prefer my bands for arms.. I would use them and incorporate them in supersets.
The best pumps ever...