LINQ: When to use SingleOrDefault vs. FirstOrDefault() with filtering criteria

Question

Consider the IEnumerable extension methods SingleOrDefault() and FirstOrDefault()

MSDN documents that SingleOrDefault:

Answer 1

One thing that is missed in the responses....

If there are multiple results, FirstOrDefault without an order by can bring back different results based on which ever index strategy happened to be used by the server.

Personally I cannot stand seeing FirstOrDefault in code because to me it says the developer didn't care about the results. With an order by though it can be useful as a way of enforcing the latest/earliest. I've had to correct a lot of issues caused by careless developers using FirstOrDefault.