There has been a lot of discussion on this subject, and I don't think you can absolutely say that set-in necks or neck-through-body
construction is better. I some ways in can be worse -- not for the sound or response of the instrument -- but for doing repairs
and set up. Obviously with a bolt-on neck you can remove it for repairs (a big advantage when re-fretting), and you can shim it if
the truss rod adjustments alone are not giving you the ideal string relief and action.
A good bolt-on neck that fits snug in the body pocket works really well, and that's one of the reasons that Leo Fender went
this way when getting his guitars on the market.

Check out my web site at :

http://members.home.net/wilkatguitars/

and you'll find both bolt-on and neck-through-body construction because they both have special appeal. However, today's
bolt-on necks also give super access to the last fret, and that was one of the reasons that earlier players often preferred set-in necks.
With the latest models of bolt-on, there is no disadvantage any more.

Regards, Bill