Well... the modern Warwicks have a different look, feel, sound. Necks are usually bigger, headstocks aren't carved, pickups are MEC (a cheaper alternative to EMGs at the time), they also used a different glue in late 90s to early 2000s to save money. Now (in the last couple of years) it looks like Warwick re-gained the attention to details so probably a 2013 Thumb won't be so bad. But still, the 80s ones were almost handmade by a handful of skilled artisans while the new ones are completely CNC made. And there's also a difference for the hardware: the old ones have brass parts, the late 90s/early 2000 have alloy parts. Not sure about the latest production.