I used in the past. I paid for the app but I don't use it anymore. It is legit and all but I found it to be super slow even using it with an M1 Mac mini and an iPhone 14 Pro.

I got my 14 Pro from a T-Mobile store last weekend. The rep had no problem transferring my number to the eSim card.

I was intending to get the Pro Max but ended up with the regular sized one and I am so glad. It feels like the perfect size and easily fits in my pocket. When you pick up both phones you will know what feels right for you.