I agree in some point that new aircrafts are very appealing, giving the passenger a good impression of the airline and so a bigger feeling of safety, although they're also affected by technical problems, like any other machine in the world. But just because Jet2's aircrafts are older doesn't mean they are unsafe. In fact I don't recall any major accident, thankfully and no pilot would fly a plane if it wasn't airworthy. plus there are far older airplanes flying for far bigger airlines, like Delta and their 35 years old DC-9's, that keep on flying 3 hour sectors everyday and I don't see that much bashing over them?
And if it's just because the interiors, I guess the new make-over will do it.
I'm curious though on how long Jet2 is planning to keep these aircrafts, to make the interior change and the winglets worth it.