First let me say I love my trike, I have a Zoomer Elite with the horizontal handle bars.
Not knowing much about bike derailleur requirements I would like to set my Zoomer Elite up with some trigger shifters similar to the Shimano Rapid Fire shifters on my mountain bike. When choosing some shifters what should I consider when choosing them? What shifters will work with the Zoomer's derailleurs? Are SRAM and Shimanos road or mountain bike set ups the same for both the front and rear derailleurs as long as I choose the ones compatible with a 9 speed set up?