Thanks for that - I knew the answer would pop up straight away! I have just sold on a Silver Series Precision, as it happens, and it did have a 40mm wide neck. Nice as that was, I believe the JV series are an extra bit bit special, though? I think maybe I should try and have a go on one, see what I think of the neck, before spending out on one. Although Leeds maybe a bit far, Luke - you don't come down south at all, do you?
In terms of the components etc, are the early big Fender spaghetti logo ones any different to the later ones? I know they are a bit rarer.