To a physician or HT recipient with vertex HT experience,

I am curious if transplanting hair into a thinning vertex area is a riskier procedure than say transplanting frontal recession ?, I have had very good results with 1200 frontal grafts and have a thinning area in the back, however NOT bald yet.

Propecia has kept things somewhat in check but I would like to avoid having the swirl area become a bald spot. Would new FU's open a can of worms in that area and cause great amounts of shedding ? Or is there a good success rate ?

Often HT is in the frontal regions (admitedly for good reason).

I am 41 years old
What is your advice ?

Thank You