I wonder too about the effectiveness of this splitter since it doesn't extend forward of the bumper very far. Something longer and lower would certainly be subject to wear but perhaps you could attach a track day or One Lap splitter to this or directly to the bumper. The longer and more effective the splitter is the more you'll have to support it which complicates things.
Here's an example of a Lotus owner and his homemade splitter.
http://www.trackjunkies.org/topic/25...ade-splitters/