What makes this title so collectible ? Is it the theme or ?
This one should turn out really well by the looks of it .

Theme is the MAIN reason for me as I love my oldskool surfing and memorabilia and also it plays like a demon too! definitely one of the better EM's out there IMO and also one of the last as it was manufactured in 1976 if I remember rightly. EVERYBODY needs at least one old girl in there collection, I have 3 soon to be 4!
There are also very few surfing themed pinball out there that I am aware of
SURFER which is the same GTB but 2 player and IMO a much better back glass
SURFING by  SEGA very rare and only a few made in Japan would like to play and own
and also a 1967 SURFERS by BALLY , bloody ugly and a pig to play IMO but hey you never know I might get one?