I do not understand very well what he means by "what to expect from the Meets". I suppose that in terms of its operation, if so, there are many recorded glitches (do not panic, only spoils the device one of them: when it send you an bug mail with the green background and you delete this friend), but if the values are reset factory, there is no danger (this glitch ir very rarely of appears). Anyone can make you lose all your progress in the worst case. Even so, not all tamagotchis are affected by failures and some people have managed not to repeat them.
As for the corroded batteries, I never heard about ketchup. But yes about rub with a toothbrush and baking soda, or a cotton and vinegar/lemon (although I have not tried it personally and I can not assure you anything).
Congratulations on your new adquisitions! The IDL is a great version.
