Well, yes, it's madness on the level of 'how many angels can dance on the tip of a ball-point pen?' Because different agents have different statistics, and those are constantly shifting. Bigger agencies might not have a 50/50 sell rate, but they can take chances on many more manuscripts. Small boutique agencies may be choosier, but they can dedicate more time to finding the right publisher.
One agent who has my partial right now says she sells nearly every project she accepts. The other agent is new, but has great connections in my genre.
It all boils down to this: do you feel a particular agent has the connections, perseverance, and enthusiasm to give your baby the best shot it can possibly have? Don't sign with the first agent who asks, if you have any doubts.
It's been said on AW many time, in many forums: a bad agent is worse than no agent at all. Publishing slots are so rare now, that even great agents can have problems placing great books.
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