It sounds like there is a wide range of experience in HA longevity. It is worth getting some data on this for the benefit of everyone. Several experiences suggest it may last longer than the 12-18 months claimed
1. Your brand of filler (i.e. juvederm, HA) or PMMA/ Elanse some of the data will be useful but not all.
2. Injected amount
3. Dimensions before
4. Dimensions after
5. Time in months until swelling diminished
2. time in months until you lost 25% after swelling is gone
3. time in months until you lost 50%
4. time in months until you lost 90%
5. time in months until you lost 100%
6. Simple yes no on if it your Dick went back to its original state.
If you got a top up you have to start again at 1.
Should be able to do some in interesting stats on that with enough data