I think that an under belly panel will cut more drag without adding to the frontal area, but it is also much simpler to make/maintain a front dam. Mine held up alright, but in the future I'd probably go with aluminum for better durability. I ended up selling my Festiva back to my dad and he took the panel off, but it was still fully intact and working as intended after about 8 months. I figure I broke even or came out a little ahead with fuel savings, but I had fun doing it, so there's that. I'd do aero wheel cover and rear wheel skirts either way
