I see about a 15% increase on a Radeon R9 380X (175 h/s vs 200 h/s)and about a 35% increase on a Radeon HD 7870 (125 h/s vs 175h/s) using Optiminer. However, I've found Optiminer to be far less stable than Claymore. I've been having to restart it every 3-4 hours and I'm also seeing "block" pixelation pretty consistently while Optimer is running. I do not have these issues with Claymore and for that reason I've switched back. At this point in time neither application is perfect, so pick your poison. I'm hoping Claymore's next release can match (or exceed) the speed of Optiminer while remaining a stable build.