This question is solely about using these technologies against stored procedures.
I've been doing quite a bit of reading on pitting these two against each other, and far more than anything I've been seeing them compared with CRUD operations and other more complex queries - very rarely for calling stored procedures.
I've read that it's hard to beat ADO.NET for performance when calling stored procedures. However, when calling them with Entity Framework 4.1, you get the benefits of entities (rather than just the data reader) which can be nicer to work with and pass around (imo).
I ran a few tests today (not sure of the accuracy of them) and they suggest that over 100 or 1000 iterations, calling the same procedure, that ADO.NET is something like 5 milliseconds, on average, faster per call. (I haven't been able to test how long it takes to convert from the standard data reader object to a similar kind of entity, but I doubt it makes up for the 5 milliseconds)
Is it worth the trade off in performance for the benefits in design and writing? Or are those 5ms per query just too much? Does the answer change between small projects, and environments like e-commerce?