Does Silastic Implant for Rhinoplasty Look More Fake Than Cartilage?

I find it very difficult to believe you do not have enough cartilage on your ears (plural) and/or septum. If your deficit is that large, it is most likely you will need a substantial graft which is traditionally your rib (hip bone and skull have also been used).
The size of comparable silicone or PTFE (gortex) or polypropylene (medpor) implants to achieve a comparable augmentation would most likely make it more prone to complications, either visibility or rotation, encalpsulation, extrusion, body erosion, etc. Silicone is probably the most coomonly used material and therefore it s complications are frequently described. It is not likely to be permanent. The search for the perfect implant has gone on for over a 100 years. People have even used ivory. However, the perfect implant has not been found. Implants which are the "rage" today may not prove to be ideal in the future as complications arise.

I have successfully used preformed nasal implants for years, but to answer your questions:

1. I would not plan on anything lasting a "lifetime".

2. Whether cartilage, bone or a pre made nasal implant are used, the skill and judgement of the surgeon is the primary factor. ie. the most important part of getting a good result, is the surgeon you choose.