What is the big deal with...

adamantium hearts? and the other hearts for your android? Why do ppl want the hearts so bad?

I thought androids were not worth having??

They have slots that can be scrolled with any scroll, like I said in your other thread.
The higher the rank, the more slots it has.

It's a cheap way to get a slight range boost. The hearts only last 2 weeks though, so you have to buy or make a new one when your current one expires.

wow, for just that, it seems quite strange how so many want the recipe for it...

and the rank? What does that do?

recipe once learned, you can make infinite amount of hearts only for the addy and gold one i think

It's infinite for any type of heart. If you're smart you buy the recipe, mass produce hearts, and sell them off in the FM to people to get back what you spent on the recipe so it basically cost you nothing and you can re-make your heart every time it expires for next to no cost.