Just to chip in a little. I have actually tried the full range of Final Audio Piano Forte models and like what EveTan said they do have the same sound signature as they have the same internal construction and only the material used for the metal housing is different.
Personally I dont believe they are the best but that is just my opinion as they tend to be a little too bright for my taste. If you are considering the Piano Forte X do note that they are quite big and heavy so if you have small ears I would recommend you to stay away from them.
If you have a big enough wallet to afford them I would suggest looking towards other flagship universals (Senn IE800, Shure SE846, AKG K3003 etc.) or even consider customs (JH Audio, Westone, Heir, Unique Melody etc.).
My favourite for universals would be the IE800 while customs it would definitely be my Fitear C435.
Do take a look at the other earphones review threads to see what others think about all these earphones before making the jump!(: