Re: how much better is this?
the only solution to the tensioner problem is to get rid of it entirely. this can be done with shims at the rear motor mount (like Norm at Venice sells) or by changing pedal side sprockets to equal the drive side.
there are some bikes where there is no solution, and your chain will drag across your frame, and will eventually eat through it unless it's elevated with a tensioner. (it may take awhile, but it'll happen.) if you can't space the frame out enough, the only cure is to get a different frame.
in my opinion, the only proper placement for the kit-supplied tensioner is in the trash.
drilling holes, tightening it till it crushes the chainstay, JB welding, rubber, or anything else is just a band aid, and like a band aid, it's gonna rip your skin off when it comes off.
i think the real problem is when it becomes a "chain guide." if your chain isn't aligned true from motor to sprocket, bending the tensioner isn't the answer. chains don't turn sideways. the torque is what will pull it into the rim.
i don't use any tensioners on my builds, and have removed them from other people's bikes. about ten different frames in all, and i've always found a way to make it work without one.
this is a "debate" that won't go away, as long as those spoke-killers are still included in kits.