Dealer repairs or local specialist

So I have just bought a 1998 discovery 4. It’s always had the main dealer servicing and repairs. I’m just wondering if I should continue to use main dealer or if I’m ok to use a local specialist? The nearest one to me is RCV, but this being my first landrover, I don’t want to affect the resale value if I don’t take it to the main dealer.

1998 or disco4 it cannot be both?
RCV are okay.