The Jet2 737-300s I flew in to and from Rome last summer were very tired looking aircraft. I got a good look at the exterior as we walked from the airbidge to the aircraft in the rain (love that low cost service!) and I wasn't impressed.
Speeds can vary for many reasons. We quite often bump up the cost index to make our arrival time - which makes commercial sense if there are connections which would be costly to the company if they aren't made. Also, I remember slowing long haul trips back to right down not to arrive during the curfew and incur a heavy increase in landing fees.