i THINK MOST OF THESE VENDORS ARE SELLING THE SAME MANUFACTURER'S WHEELS, (sry caps) and yes the plastic lug covers screw onto the lug nuts,(you have to have correct lugs) 245/50/16 all around is preferred by a few. make sure u get 4 "fronts" offset spacing all around. I'm not sure if they always come like that. I buy all my tires from tirerack.com
u get them fast, kumho's are very inexpensive tire, real soft, hook good, quiet ride, i think i paid like 52 a tire? and they are rated higher than some well known twice the price tires.
just my opinion