Im not familiar with that benchmark, ive never used it. Honestly, i think benchmarking on phones is a very poor way to judge performance.
Why you are seeing a big difference, and why your optimus got better results is most likely due to the fact that it takes A LOT less power and resources to push the same information at a lower resolution. Higher resolutions require more memory and more GPU power to render the same scene. Just like in a computer if you drop your resolution, you will see an increase in FPS, and thats really all the benchmark is judging is average FPS and drops in FPS.
XDA Developers was founded by developers, for developers. It is now a valuable resource for people who want to make the most of their mobile devices, from customizing the look and feel to adding new functionality. Are you a developer?