Stateside the choices of LRR tires appears to be VERY limited. Europeans apper to have several more choices in LRR tires.
AFAIK and from the many threads on this topic all others (available here, USA) but the OEM Bridgestones have a negative MPG impact.
See:
Tire Comparison Test
http://www.insightcentral.net/forum/vie ... 38&start=0
IIRC there is one Michelin that reportedly has the least MPG reduction 1/4 - 1/2 of the above. There was one thread on the topic in the last year or so, sorry I don't have the link.
HTH!