I just bought my RDX a week ago and love it thus far. I originally thought I was going to buy an MDX but after driving both, I prefered the way the RDX handled and I do not need the extra room that the MDX has. Mileage is ok, been getting an overall average of 19 mpg, this should improve after a couple thousand miles. I was concerned about going to a 4 cylinder from my 06 TL. This vehicle has plenty pickup and absolutely no turbo lag. The engine is rather quiet too from the inside, as opposed to how noisy it is on the TSX.
Tech package is a must! Nav package is great and back-up camera works pretty well. Sound system is great! I recommend getting the auto dimming mirror, rear area rubber tray and the rear bumper appliqué to help prevent scratches from the bumper when loading/unloading.
Auto headlamps, bi-level xenons as opposed to only having low beam xenon with halogen high beam, auto dimming mirror, power passenger seat with lumbar support, ventilated seats (Acura doesn't offer this yet).