Just wanted to post a list of the good and bad cards from Team Rocket!

Fighting
Good:  Diglett, Dark Machop, Dark Machamp (all get around resistance!)
Bad:  Dark Primeape

Water
Good:  Dark Blasoise, Psyduck, Dark Golduck
Bad:  Dark Wartortle

Psychic
Good:  TR Abra, TR Drowzee, Dark Kadabra
Bad:  TR Slowpoke, Dark Slowbro

Electric 
Good:  Dark Jolteon
Bad:  Dark Electrode(worst of 3, that's really saying something!)

Fire
Good:  Dark Charizard(much more realistic attack than Base)
Bad:  Dark Charmeleon, Dark Flareon, TR Ponyta

Grass
Good:  Dark Muk, TR Oddish
Bad:  TR Zubat, Dark Golbat, Koffing, Dark Weezing, Dark Gloom

Colorless
Good:  TR Dratini
Bad:  Dark Persian, Dark Dragonair(who uses multiple evolutions ne way?)

Trainers 
Good:  Rocket's Sneak Attack, Challenge, Nightly Garbage Run
Bad:  Here Comes Team Rocket, Digger, Sleep!

Energy
Good:  Rainbow Energy, Full Heal Energy, Potion Energy

Hope this helps... have fun!
Aaron