I've had both to some extent. I bought the bike 8 months ago with the original style Tourances and what I estimated to be about 30% tread left on the rear, unknown age. After about 6 months and 5,000 miles, I decided it was time to replace the rear because it was pretty squared off and at mimimum safe tread depth. I wanted the original style because I have heard that they wear longer. My prefered shop said they could only get the EXP model, so I got those - front and rear.
I have to say that the new tires handle markedly better than the old. Mind you, this is a new tire to old tire comparison, not new to new. The old front tire tracked badly in "vertical" groves in the road, the new tire doesn't notice those grooves.
Cornering in general is so much better. The old, squared off rear decidedly tipped into turns. The new rounder one has no transition effect. The EXPs feel stickier as well. Stickiness and longevity are generally mutually exclusive. I don't have a tread depth gauge, so I can't tell you how much I've worn off in the last 2,000 miles, but it's not visible to my untrained eye. If I get 10,000 miles, I'll be happy with that, given their very good pavement and dirt road manners.
'04 DL650 - Blue, 57,000 miles, well personalized, gone but loved
'08 WR250R - Goes anywhere
2012 Yamaha Super Ténéré - makes the DL redundant