I'd have to say the best investment I ever made in a socket/wrench set was
my Metrinch tool kit. One set of sockets/wrenches that do double duty
(metric AND those damn US fractions).

http://www.mitools.com/main.html

Not affiliated with them, just a very happy customer.

Sean B.
'90 V'gon, "Happy Bus", pseudo Wolfy
Torrance, CA
http://vgonman.vwtrek.com