What a bunch of crap?  The VOR antenna mounted in the wing tips can have a limited range when used with the winglets.  Since the winglets are partially made of carbon fiber, you also have a signal blanking effect when at certain angles as to the ILS or VOR signals you are attempting to receive.  You want the maximum signal?  Use the external antenna.  If you're satisfied with the possibility of reduced VOR reception when using the winglets, use the internal mounted antenna.  Oh, one more thing, signal stregnth is greatly reduced when any metallic object, including wiring, is placed near and in particular on top of the wing tip mounted VOR antenna.  And that ain't no crap!

Joe Bartels