Linq: SqlFunctions.PatIndex vs string.Contains for string comparisson

Question

Which of the following versions for the same query will perform better:

Version 1 (string.Contains):

var query = db.Products
    .Where( p => p.Description.Contains( description ) );

Version 2 ( SqlFunctions.PatIndex ):

var query = db.Products
    .Where( p => SqlFunctions.PatIndex("%" + description + "%",p.Description) > 0  );

Answer 1

I believe version 1 runs faster theoretically.

Reasons:

1. Both versions translate into SQL queries eventually.
2. Version 1 translates into a query with where clause having 'like' operator
3. Version 2 translate into a query with where clause having 'PatIndex' function.
4. We know function in SQL will take longer time to return results when comparing with pure 'like' operator in large data set.