There is no such thing as an electric knife sharpener that will not eventually ruin a knife, if it used constantly. They should only be used to put an edge on an abused knife. After that, I use 2000 grit autobody paper glued to glass with "3M" temporary spray on glue at 22' to keep the edge on my knives.
However, right now and until they run out of sharpeners, TUESDAY MORNING Stores have real good professional electric sharpener: MSRP:
$160.00, now $49.99, "Waring Pro".