Hi Roger,
My 2018 Cube Reaction pro, with 500wh battery + a 400wh battery, has done 12,500 miles & has only needed a replacement drivetrain & service (£140) ~every 4000 miles, plus a couple of wheel bearings in the 3+ years I've had it.
My riding is all on Cornish byways, lanes & cycle tracks, potholes included at no extra cost.
Following its recent annual service it rides 'zackly like it did when new, other than a light, occasional click from the forks.
That's why I'm trying to buy a new one!
