You list 2 pro-points for sprocs:
Performance - not really. In Sql 2000 or greater the query plan optimisations are pretty good, and cached. I'm sure that Oracle etc do similar things. I don't think there's a case for sprocs for performance any more.
Security? Why would sprocs be more secure? Unless you have a pretty unsecured database anyway all the access is going to be from your DBAs or via your application. Always parametrise all queries - never inline something from user input and you'll be fine.
That's best practice for performance anyway.
Linq is definitely the way I'd go on a new project right now. See this similar post.
