The key is the finish temp with a beef tenderloin. You can cook it at almost any temp as long as you take it off at the right temp.
If you cook it at 350 I think you'll find that you don't need to sear. You'll also have some meat at the ends and on the outside of the roast that are cooked more than the inside. Nothing wrong with that, but that's how it will cook at that temp. At lower temps you'll get a more even degree of doneness through out the roast.