Which SME? If you have the FR headshell just try it.
I use a heavy head shell on a 3009/II for the same reason: add mass. It requires more weight at the back too, to balance. The added weight at both ends loads the knife-edge bearings down more firmly. The arm now plays low-compliance MCs beautifully. That was the knock on the 3009, back when MCs took over the 'high end': moving coils don't 'like' it. With these two simple mods, they like it fine.
I use a heavy head shell on a 3009/II for the same reason: add mass. It requires more weight at the back too, to balance. The added weight at both ends loads the knife-edge bearings down more firmly. The arm now plays low-compliance MCs beautifully. That was the knock on the 3009, back when MCs took over the 'high end': moving coils don't 'like' it. With these two simple mods, they like it fine.