If you look at a typical Google search result page, you’ll notice that Google does not display the page title beyond 65-70 characters. Therefore your title should fit within 65-70 characters and anything beyond that will be cut off by the search engine.
Bing search engine may not be showing all results in a typical search as demonstrated in this search exercise. The results may be biased in Microsoft’s favor. So how can Bing help you make decisions?