Expert Belt Rotom-W is a pro set, which blarajan has introduced to me. Choiced Volt Switch seems iffy in tiers with plenty of Ground-types and Electric-immune mons, and being stuck in a -2 Leaf Storm is a momentum killer. That's the major issue I have with choiced Electric-types, despite their amazing revenge-killing capacity.
Specs sounds powerful, but EB is probably more useful despite the drop in power.
Rotom-Mow once surprised me with a last-minute Rain Dance for a Swift Swim boost on his last-mon Omastar; I didn't see it coming since his team didn't scream RAIN DANCE. It was definitely a nice set-up :d