There are actually a number of multi-compound tires out there right now, not just the RoadSmart and the PR2. As for speed of wear on the front tire, I suspect the Dunlop is in the same boat as my Pirelli Corsa lll's. The Corsa lll is also a multi-compound tire, but only on the rear. The tire compound is a mix of a harder, higher mileage compound in the center, and the shoulders of the tire are the same compound as the Super Corsa sport tire. The front, however is not multi-compound, and is the same compound as the Super Corsa.
When you examine the Dunlop website, they claim the rear RoadSmart is a multi-compound tire, but make no reference to the front being the same. I suspect the front is the softer compound only. Not that this is a bad thing, but it explains the expiration of both tires at roughly the same time. (as noted by HaulinAshe in another thread.)
Quote from the Dunlop site:
"MT-Multi-Tread compound
rear tire incorporates a long-wearing compound in the center of the tire tread and a lateral-grip compound on each shoulder to maximize cornering performance and provide class-leading grip and feel."
Dunlop clickage
Now, if you look at the Michelin site, both the front and rear are multi-compound. However, the front and rear use a different combination of compounds. They have a nice little visual chart, too.
Also interesting to note is that Michelin claim superiority in wet traction and mileage, but does so based on an independent test done in 2006. The RoadSmart arrived in the first quarter of 2008, thus it does not appear on the comparison.
PR2 clickage
Though probably not the best suited tire for the FJR, Bridgestone has a new BT-016 tire that actually incorporates 3 compounds on the rear tire and 2 on the front. I will probably try these next on my little FZ.
Bridgestone clickage