Kites rip for lots of reasons, you might have had a small shell cut in the sail where it tore and when you crashed the extra load made a big hole.
Be very thankful that SS are going to repair it, they probably don't have to and will be doing it as a goodwill gesture to you, to show you they support their customers.
If the repair is done by Neil at Hold the Line Kites in Wembley it will be as good as new and resale value will hardly be affected. However if you are not selling the kite there is no issue about resale value and I don't know why people say that??
Maybe its becasue some people bargain hard when they buy a used kite with a repair in it??

Straight rips from LE to TE in the sail are nothing, they never affect how the kite flies and are usually easy to repair and easy to make the repair near invisible.