I'm still running the Vortex Generators along with the 8" Sheridan rear spoiler. To balance this out, I have a low front air dam with a splitter.
Some pics showing the aero mods front and back
For the small cost, you might consider trying them out before going to a big wing.
You can order them here
AirTabsI had to put on a somewhat large splitter to balance the downforce on the front. I made these out of fiberglas for along time, but switched to 1/8" fiberboard because it's just as light, cheaper and more durable.