I called the Garmin help line and this is what was decided for the most economical IFR set up. The North America bundle for the G3X is 199 dollars. The North America bundle for one GTN 650 cost 549 dollars. Total 748 plus taxes. Add the Garmin Pilot premium, add additional 150.00 so total out the door is 900.00
The One Pak would be beneficial if you had duel GTN systems or TSO units like the G 500 or G1000. Also if your using a Garmin portable unit along with everything else. The One Pak is 925.00 and upgrades you to the premium Garmin Pilot, but you still need to pay for the 75.00 base subscription, so your total is 1000 dollars. The price can be trimmed a little if you select the U.S. data base vs North America. Saves 50 dollars.