Dr. Brassard and dr. Preecha offer similar technique, penile-inversion with scrotal graft. How much depth can you expect is largely dependent on the size of your penis, whether you are circumcised or not, and if you are not, you will maybe have a chance to choose whether you feel the depth is more important or looks. This would differentiate in whether penile prepuce is used for inner labia minora and hooding, or is it used for extra vaginal depth, in which case urethra would be used for inner labia and hooding, or both could also be made from penile skin. Penile prepuce will generally give aesthetically better result for inner labia compared to using urethra or skin from penile shaft. Im not shure if Brassard is able to give you this kind of options to choose, but Im 99% surgeons from PAI institute will. If you have a really large penis you can likely expect 6 inch maybe even slightly more from both options. If you are in about average size, you can still expect decent depth, which around 5 inch definitely is. If you are smaller than average, and depth is very important to you, you might want to look into other options, like Chettawut and Suporn.
Both Suporn and Chettawut will be able to achieve 6 inch depth. Suporn guarantees 6 inch minimum because of his "meshed" scrotal graft. Chettawut uses normal scrotal skin graft for vaginal wall, which means he is sometimes not able to achieve such depth without using additional skin graft from groin, or abdominal area. Again it depends on what you start with and how much scrotal skin is available. It might well be enough for 6 inch or more... You wont be able to know exactly how much to expect unless you have personal consultation with him. In any case 6 inch is achievable.
