Superior's own tests show that the tips of their needles stay sharper almost fives times as long as needles which are not titanium tipped. Although these needles cost approximately twice as much as other brands of needle, they last nearly five times longer so definitely make economic sense. Clicking on the image below will take you to the page on the Superior website which explains this in more detail.
You can order them for worldwide delivery direct from Superior Threads. If you are a stockist or know of other stockists in your country, please leave a comment for me below so that I can update the post. And if your local quilt shop doesn't stock them, go in and demand that they do!