I had the 7/125 on my 2003 Caravan. Paid for a new transmission at 75K miles along with a waterpump, window regulator, lift gate motor and struts and probably some other things.
I have the Lifetime Unlimited mileage on my 2010 Town and Country. I doubt I got my money out of it at 125k miles but since it is lifetime I'm not too worried about it. It is going in this week for sliding door lock replacement.
I have the 8/125 on my 18 3500. So far the only thing it really paid out was a rental car when the Trans Control Module went out but that module was covered by the 3/36 and 5/100 warranty. I do need to get it in one of these days for de-lamination of the screen on the stereo which should be covered under the warranty.
It only takes one transmission or turbo to pay for the warranty so I like the security but these trucks are much more reliable than they were in the 200X so it is questionable if you will see the value out of it over the stock 5/100 powertrain warranty.