You bring up several good issues.  On the longevity issue, you are not alone in that fat transfer (while we all love the idea) is just not very predictable still.  As for Radiesse, I agree that the marketing is misleading in that in some people Radiesse does last 9-12 months and for others more like 4-9.  Again, a predictability issue!

As for Restylane/Perlane or Juvederm Ultra/Juverderm Ultra Plus, it's quite predictable in most people.  The Perlane and Juvederm UP are the longer lasting versions and generally will last 6-9 month.  So my first question is.....  did they use the correct product?

As for Sculptra, in my 7 years of experience, it is very predictable.  But remember while it lasts 2 years technically you don't want to go from full to zero.  So I tell my patients 1 maintenance treatment once a year and then your facial volume will be quite consisitent.  Remember though that Sculptra takes 2-3 treatments over 6-9 months to acheive that volume the first time.  It's slow to act but then low maintenance and very consistent.

The down side of using Scuptra in the chin is that it can't be injected close to the lips because it will get bumpy there due to the action of the lips.  You still will need a little Juvederm  if you need support at the lip margins or volume in the lips.    Dr. I