There is a wide difference in the OM61x range, a 4 cylinder N/a vs 5cyl turbo are miles apart in terms of daily driving. It all depends on what you are looking for the car to do and where you drive and how much maintenance you want to do.

Live in the flatlands of Florida and take the car out to buy your weekly lottery ticket at the local convenience mart, a 240d would last you a lifetime. Daily commute in the major metropolis beltline...a 617 turbo would be a better option. If you drive a lot, you will need a lot of valve adjustments on the 61x engines. The OM60x engines dont require that adjustment process. All have their pros and cons, but start first with defining your specific needs/wants and find the option that best fulfills those later.

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Stable Mates:
1987 300TD 310K mi (Hans)
2008 Jeep Grand Cherokee OM642 165k mi (Benzrokee)

but I don't care about the 617 turbo, since everyone knows that they are more prone to have problems; I was asking if a NA617 is more durable than a 616/615 or viceversa

You have not yet defined the job you are looking to achieve. Your question is therefore impossible to answer. You asked which is the best hammer, a cobblers, framing or sledge. All will hammer, but some better than others depending on the job you need it for. Hammering is NOT a job, it is a function.

The OM61x are All fine engines, all are very durable if maintained and set to work in a job where they are efficient and not abused. All of these engines can be both utterly reliable or utterly horrific depending on what is asked of them. So until that is defined, there is no "right" answer.

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Stable Mates:
1987 300TD 310K mi (Hans)
2008 Jeep Grand Cherokee OM642 165k mi (Benzrokee)

so you mean that the number of cylinders in 61x engines doesn't matter?