It depends what you plan to do, get lots of referrals or make lots of purchases. If you're not sure, you can always join as a CrumbSaver, and if you start getting referrals you can upgrade to a CrumbEarner. (You cannot revert back to a Saver though) A crumbsaver earns more per purchase, but can only have one generation of referrals. A Earner doesn't earn as high a percentage on his own purchases, but can have 5 generations of referrals.
Oops, that was a mistake! What I meant is if you're not sure whether you'll get many referrals, you can join as a CrumbSaver (not earner) and earn more for your own purchases. Then if you get a lot of referrals in more than one generation, you can upgrade to a Earner and start earning from your referrals.
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