You are right about the first example (although the F# version looks nicer =D) But that struct example is less than great. Just last night I had a readonly C#

You are right about the first example (although the F# version looks nicer =D) But that struct example is less than great. Just last night I had a readonly C# struct like that, that I used as a dictionary key and wondered why my perf tests took a nose dive when the Dictionary hit a few dozen entries. My boneheaded mistake was i forgot to override GetHashCode and Object.Equals. Great my perf was looking decent, but even then I was allocating 32 bytes of memory on every lookup. I forgot I needed to also implement IEquatable<> to prevent boxing on calls to Object.Equals. My little 2 item struct is 3 lines of definition and 7 lines of boiler plate to get it right. and my GetHashCode impl is suboptimal. F# records do all of that for you. every time. automatically.