This is only here because the text recognition thing is (temporarily, I hope) preventing me from posting comments on my own blog.
The article mentions the models, but doesn't describe them except in vague emotive terms, so I can't tell you which one I subscribe to! Put me down for whatever the Guatemalans are doing.
Quoth Marco: Let me try another tack. This other article Cupidity mentions four competing yet incompatible models for the economy of the baby "industry". Which do you subscribe to and how would the caliphate fit into a world with other models in play? Could desparate parent wannabe's travel there to buy a spare to make profit for the Mahdi? Could desparately poor parents sell their babies for cash they need to feed their macadamia nut habits? Could parents whose children are in the mujahideen's army change their mind and get them back? Could youngsters have unprotected sex with gay abandon because the fedayeen would foot the bills for any resulting children and forced sterilisations? What happens if the burden of dependants overwhelms the system? Or the opposite - if youngsters become risk averse and birth rate drops through the floor? What cracks first?
To answer your questions: Yes, yes, yes, and no. Remember, these are supposed to be good Muslims, or good members of traditional dhimmi religions with decent values. The burden of dependents won't become too great because they will be supported by the productive labour of the older generation of dependents- this is not quantitative, but it would definitely be an improvement on the situation where both the young unwanted underclass *and* the working-age unwanted underclass form a welfare burden on society.
The birth rate is unlikely to fall through the floor, because the prevailing ideology of the society is optimistic and philoprogentive- it is societies without such ideologies, overcome by mindless nihilism and despair, like Europe in the 3rd and 21st centuries, that suffer such calamities.