Latest issue of Handloader magazine has a nice review of them, if you want to pick it up at a newsstand.
Conclusion:
Flatter shooting as should be obvious from higher BC. As designed. Makes for good/better 200 yard shooter.
When coupled with the newer LR powders, there is an increase in velocity over traditional powders. As designed, without necessarily an increase in pressure (not tested).
Terminal ballistics (penetration and bullet performance) not tested as I recall.
Grouping improvement vary (30/30, 45/70, and .338 Marlin Express tested; mix of Win and Marlin rifles).
LRs are more expensive than the typical JHP bullets, and mostly for that reason, I just use the 300 gr. JHP in 45/70 at ca. 2000 fps for a good 200 yard brush gun.