You're gonna have to back that up with some evidence to have that fly around here.
My testing, although not side by side, indirectly led to the exact opposite results. I used a PD for about two years almost daily. On the days I did not use it I was using the SSV. My testing between the two was interesting. The PD needed three stems to get me there. The SSV could do the job just as well, but quicker, with the same three PD stem's worth of herb in it at one time. So if I waanted to take my time I would use the PD and if I wanted a punch to the face I would use the SSV. However, the SSV didn't perform well at all with just one PD stems worth of herb...it needed at least two stem's worth and worked best with three.
When I got the Cloud I immediately mothballed my SSV. The Cloud was a heavy hitter that tasted better and hit harder with water filtration...who wouldn't want that! But I still used my PD to slow it down on most days. Then I tried the Cloud with three PD stem's worth and got the same great results that I got with the SSV. Later I tried the Cloud with one PD stem's worth and got a really nice cloud.
So while the SSV and Cloud are both heavy hitters, my testing led me to believe that the Cloud could still be used with a small, efficient load, whereas the SSV required more to perform and therefore couldn't be used as efficiently. Just for kicks and for a size comparison, it turns out the ELB fits snug inside the standard wand of the SSV.