Magneton

At first glance, it may seem like Magnezone, with its superior bulk, completely outclasses Magneton. However, this is not entirely the case. Magneton's base Speed is higher than Magnezone's by 10 points, which actually allows it to outrun Darkrai, Shaymin-S, and Jolly Choice Scarf Tyranitar when Magneton holds a Choice Scarf; this is actually a pretty huge advantage as it allows Magneton to revenge kill these Pokemon, while Magnezone will not be able to outspeed the aforementioned threats with a Choice Scarf. However, because of Magnezone's greater bulk, there is no point to employing Magneton for any other purpose in Ubers other than a Choice Scarf user, as Magnezone WILL use any other set much more effectively.