Factory Sportline has a slightly smaller steering wheel, closer ratio steering, lowered sport suspension, wider lower-profile tires and recaro seats front and back -- handling is excellent, on a par with my C43 AMG (but without the power coming out of curves).
190E backseat is smaller than the 300E and the steering coilumn doesn't adjust (my only gripe). Sportline seats are not for widebodies -- my 95 LB, 5'1" daughter fits perfectly (it's her car).
80MPH on highway is fine but engine revs high and can be a bit noisy -- best for zipping around in town.
If possible, look for a '93 Limited Edition 2.6 -- rare, as only 700 were made, but all 190E options + factory Sportline + special black paint and leather (black with red panels and piping) + factory debadged.
'98 C43 AMG
'93 190E Limited Edition (including factory Sportline package)