Probably one of my fave parts about Gengay now is that even WITHOUT Special Attack EVs and WITH a Special Attack lowering personality, its Special Attack (max) is 267, which is above average. Awesome.
Blissey dais to Gengar. Skarm dais to Gengar. Snorlax dais to Gengar (sometimes). Ludicolo dais to Gengar. Umbreon dais to Gengar.
Even if you have to resort to using Shadowpal a couple times, it can lower Special Defense, which ROX with T-Bolt.
BTW, go ahead and lock. Only nubs can argue against Gengar being good