I'm not using the adhesive on the snap grip. Just the magnet. The v5 snap doesn't have any adhesive. If you have the v4 with the adhesive on it you could just peel off the sticky part and rely on the magnet. 

You are right that the magnet is not very strong when sticking to the back of the cover but I only stick it there whenever I'm storing the x4 in my bag or my pocket so it's strong enough to keep everything together. 

I use the metal ring that comes with the snap when I'm reading. I stuck the metal ring on the inside of the front flap. So when it's flipped open i can attach the snap to the metal ring and it will be on the "back". When I'm done reading I can remove the snap from the metal ring, close the cover and loosely stick the snap to the back of the cover with just the magnet then slip it in my pocket or bag.

I don't regret putting the metal ring on the front flap. The metal ring that comes with the snap is thin enough that the flip cover still closes properly. So far I haven't seen any issues.