My off-the-cuff experience says Bing and Google are about the same for the searches I run. I see no reason to choose one over the other, yet.

But Microsoft could compete in non-search areas if desired. Specifically (a) fewer ads and (b) better privacy guarantees. Not clear the customer base cares enough about either of those issues to switch, but Microsoft has a lot less to lose so they can at least afford to try.