SINGLE PLT OF SMA HAS IFR TRACK DEV WHEN CONFUSED BY CONFLICTING INFO ON INDEPENDENT GPS UNITS.

Narrative

I HAD FILED AN IFR FLT PLAN FROM SGR TO ERV USING THE INDUSTRY 2 DEP TO IDU THEN V68 TO MARCS INTXN; DIRECT TO ERV. I HAD JUST RECEIVED THE GARMIN 396 AND HAD PROGRAMMED THE CORRECT WAYPOINTS BEFORE LEAVING MY HOME FOR THE ARPT. PRIOR TO LAUNCHING; I SET UP THE GARMIN 530; GARMIN 430; FOR THE IDU DEP; WHICH ALSO INCLUDES THE CENTEX VOR AFTER DEPARTING IDU. ALL WENT WELL UNTIL REACHING IDU; AT WHICH TIME I FLEW THE HDGS SHOWN ON THE GARMIN 530/430; AND WAS COMPLETELY DISTR BY THE GARMIN 396; WHICH WAS SHOWING ME R OF V68 TO MARCS INTXN. I CONTINUED TO FLY USING THE GARMIN 530/430 AS MY PRIMARY SOURCE OF NAV WHICH WAS DIRECTING ME TO THE CENTEX VOR (CWK) (WHICH SHOULD NOT HAVE BEEN A PART OF THIS FLT PLAN AT ALL) AND WAS DISTR WITH THE CONFLICTING INFO SHOWING ME R OF COURSE ON THE GARMIN 396. WHEN I REALIZED THAT I HAD NOT PROGRAMMED THE MARCS INTXN INTO THE GARMIN 530 OR 430 AND WAS NOT USING EITHER INSTRUMENT IN THE V-LOC MODE 'FROM IDU;' I IMMEDIATELY SET UP THE 530 ACCORDINGLY AND CORRECTED MY HDG TO INTERCEPT V68 (259 DEG RADIAL FROM IDU). ZHU ASKED IF I WAS MAKING THE CORRECTION TO INTERCEPT V68; AND I CONFIRMED. HE THEN COMMENTED THAT WHEN HE SAW ME OFF COURSE AND MAKING TURNS; AND BECAUSE HE WASN'T SURE WHAT I WAS DOING; HE HAD INSTRUCTED A JET TO LEVEL OFF AT 13000 FT TILL HE COULD DETERMINE WHERE I WAS GOING. THE NEW GARMIN 396 CAUSED MORE OF A DISTR THAN ANYTHING. ALTHOUGH IT DID HAVE THE CORRECT ROUTING PROGRAMMED; I WAS USING THE GARMIN 530/430 AS PRIMARY NAV; WHICH I HAD NEGLECTED TO REVIEW FOR CORRECT INFO AND SET UP AFTER THE FLT BEGAN. AFTER TAKING THE GARMIN 396 OUT OF THE LOOP; AND GETTING BACK TO BUSINESS USING THE GARMINS 530/430; THE FLT WENT AS PLANNED AND WITHOUT FURTHER DISTR. I FEEL THAT AS I BECOME MORE FAMILIAR WITH THE GARMIN 396 IT WILL BECOME AN ASSET AND NOT A DISTR. THIS LEARNING CURVE SHOULD OCCUR EITHER IN THE 'SIMULATOR MODE' OUTSIDE THE AIRPLANE; OR WHEN ANOTHER PLT CAN BE PIC.