I use mine as a third key I have hidden it in the truck. It has always worked for me when needed. It's a comfort to know it's there and it saved a lot of money.
I was at about 40,000 and had a side puncture that couldn't be repaired. I went ahead and bought a new set at that point. I felt I had another 10,000 on the originals.
Who wears the pants in your family? After 42 years of marriage, I just tell my wife I'm in charge and to mind her own business. It works about twice a decade.
I installed mine today. The Uplus has a vent hole on both sides. They included a small plug which i used to plug up the unused vent hole on the positive side of the battery. The negative side has the ford vent tube attached.
I had a third key set made for around $20. Their is a web link mentioned somewhere in this group to an eBay site. You do have to have both original keys to complete the programming of the new third one when you receive it, however. It's has work fine for me and I use it as an occasional spare