You have to ask, if the larger one is an egg-producing machine, why are they getting rid of her? I also have a female who's right under 2800g, but I won't breed her this year. She dropped a huge clutch and hasn't recovered her fat reserves yet. She's a massive snake, but probably won't be ready again...
All that to say, just b/c the 3000g snake is huge, it doesn't necessarily mean she's going to produce huge. All that to say:
1 - find out more information.
2 - I'd personally go with the smaller 2, especially since they're both over 1500g. You should be able to put on more weight before they go off feed this year. Good luck!

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Jeremy Conrad
bpConnection
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...Can't...stop...must...get...more...balls...