I have two older Warwicks, a 1987 Streamer and a 2003 Thumb, so both over 20 years old. They’re solid, very high quality instruments and should last for years and years. My Streamer has some fret wear but they can probably be redressed before they have to be replaced. And I replaced the truss rod two years ago, that was a 15 minute fix. Just beware that the old one-way truss rods can be difficult to find.
I got the Thumb a couple of months ago and it can’t have been played much, it feels brand new with no wear at all, just a couple of nicks in the body.
I’m still looking for another Warwick, I’ve got to have a neck-through Thumb sometime