It's worth it until you miss a payment and run in the absurdly high interest rates. Which makes it not riskless, because your risk of missing a payment is non-zero, even if you think it is zero.
And regarding having cash: if you set aside the full amount in cash at time of purchase in order to reduce the risk of not being able to pay the rates, then you did win absolutely nothing. Opportunity cost of not having that cash available for profitable investments in case of paying in cash is what could possibly be the reason for the credit variant being cheaper in the end, but that of course depends on you investing the cash and divesting just when it is necessary to pay a rate.
And regarding having cash: if you set aside the full amount in cash at time of purchase in order to reduce the risk of not being able to pay the rates, then you did win absolutely nothing. Opportunity cost of not having that cash available for profitable investments in case of paying in cash is what could possibly be the reason for the credit variant being cheaper in the end, but that of course depends on you investing the cash and divesting just when it is necessary to pay a rate.