I have never heard of anyone growing them from cuttings. All of the white sapotes I have ever seen have been either grafted or grown from seed. There is nothing wrong with trying to grow it from a cutting but the thing about growing many trees from cuttings is that they do not root easily nor do they have a good root system.
I really think you should just graft it. It will save you a lot of trouble.
If you do get it to grow from cuttings, it should be the same exact quality fruit like the suebell tree you currently have. The time to fruiting wouldnt be long because it was grown from cutting.
There are some good resources on grafting online if you dont know how to.

My guess is that seedling tree grafted onto with Suebelle scion would have a better rootsytem than a cutting grown tree. Perhaps that could be a good thing, a dwarf Suebelle tree? If you have rooted the cutting, why not try to grow it for awhile to check it's vigor? I've cuttings started from wax jambu and muntingia, both seem fairly vigorous.

please let us know how yours do,
-Ethan

I do not understand myself why they graft everything here. I am from S.America originally and back home a lot of plants are made from cuttings or air layering rather than grafting. Things like barbados cherry, guava,sapodilla. I think the few plants that are grafted are mango, avocado.They dip the cuttings in Indole-butyric acid +alcohol mixture and then these are planted in huge boxes loaded with sawdust and covered with a lid that is made of a screen and plastic to maintain a high humidity.
They have pretty good success.

Ethan, are you planning on selling your wax jambu cuttings? What color is the fruit? I am looking for a reasonable priced cutting. Right now I am experimenting in my basement with a barbados cherry and a starfruit. I had those outside in the spring and summer and they are now inside for the winter. I also have 2 guava seedlings from a big white guava I bought at the oriental store.

Keeps me busy for the winter. Can't wait till spring.

sorry Gardenfreak,
I only have two cuttings growing right now and they are both spoken for. I might try to take some more cuttings in the spring, maybe then? I bought my tree from T tropicals, it is a 'Stinark red'. I saw a picture of a wax jambu growing and fruiting in a 15gal container. It looked like it was kept cut back (topiary?) but was still producing lots of fruit. Something similar would be my ultimate goal, it is probably too tender to put it in the ground here.

Good luck with the BC and SF in the basement, are they under lights?

I do enjoy winter, but spring will be exciting. I've already started squirreling away money for a spring plant order and still have my B-day, Christmas and Valentines day between now and then....

-Ethan