Halx pretty much summed up what I would do with the sum of money (
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)
No need for a lump sum now - sure, there's no interest on it over the time they pay it to you, but even in 20/30 years, 500k is still going to be a lot of money (well, I hope so, then again I really don't know). Nonetheless, through investing the surpluss money each year, it'll build up a pretty good savings for retirement.