Most of the "warranties" I've seen cost over $3000 by the time you factor in the interest. OTOH a rebuilt transmission should be $2000 or less.
You'd be better off just setting aside some money for the inevitable repairs. When my transmission went out in 2016, I looked at it this way: Considering that almost any large SUV these days is going to have a $500/month payment (or more!), my transmission repair was the equivalent of 4 monthly payments - and since I don't make monthly payments, I was still ahead of the game for that year by 8 payments.
In 2 years and 30,000 miles of ownership, I've had to put in less than $3000 in total repairs on my '04 Suburban (or, the equivalent of 6 monthly payments.) Even if you add in the fact that I put new tires on it, that's only another $800.
Think about it this way: The company offering the "warranty" isn't going to offer it to you if they think they'll lose money. They're betting you won't have an expensive repair within the warranty time frame and you're betting you will. And if they think you WILL have an expensive repair, you're going to pay through the nose for that "warranty" so they can cover the cost.
