Generally, TI razors have harder steel and take longer to hone. It is worth the effort when you finally get there. The same can be said for other extra hard carbon steels, like the Swedish steel used in the Bergischer Lowe for example. I used to use a seven day set of TI 6/8 Eagles, but the maintenance of seven of those blades finally had me place them on the Wall of Shame.
http://www.shavemyface.com/gallery/a...9/im001064.jpg
Now my daily shaver is harder still, but at least there's just the one, and not seven of them!
http://www.shavemyface.com/gallery/a...9/IMG_0067.jpg
Chris