I'm assuming you mean Linq To Sql
For any CRUD command it's easy to profile the performance of a stored procedure vs. any technology. In this case any difference between the two will be negligible. Try profiling for a 5 (simple types) field object over 100,000 select queries to find out if there's a real difference.
On the other hand the real deal-breaker will be the question on whether you feel comfortable putting your business logic on your database or not, which is an argument against stored procedures.