Performance of SQL Server indexing
I'm pretty sure you're leaving something out:

(n)varchar(max) fields CANNOT BE INDEXED

From MSDN:


  Columns that are of the large object (LOB) data types ntext, text,
  varchar(max), nvarchar(max), varbinary(max), xml, or image cannot be
  specified as key columns for an index. Also, a view definition cannot
  include ntext, text, or image columns, even if they are not referenced
  in the CREATE INDEX statement.


Did you get an error when you tried to create the index?

Both your queries are the same because they are the same - since you can't index that field, they are both creating table scans.