Crobat
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Moderate defenses, great speed, nice attack stat. Can learn Giga Drain and other good moves.
Honchkrow
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Super Luck ability, nice movepool. Defenses aren't quite up to snuff, but everything else is good.
Overall, if you are going for a sweeper, use Crobat. His speed stat is very good. Honchkrow is more of a bulky tank or something.