The first basic question that new stamp collectors face is whether they should collect mint stamps or used stamps. Generally, this decision is made in the very first phases of collecting. It is usually a decision that is made more on impulse than on careful evaluation of the pros and cons of each type of collecting and too often it is immutable with the collector sticking to his choice of mint or used to the end of his philatelic days. The question of whether it is more rewarding to collect mint stamps or used stamps is not a question of logic or argument but one of temperament and taste. European collectors have long had more appreciation of nice used stamps, feeling that they were more collectible because they have served their postal duty. Mint stamps have been more popular with United States and Asian collectors who came to the game later and with less appreciation of the historical nuances of our hobby.
There is one area, however, where used stamps do have an advantage and that is stamps that are being put away for long term investment and conservation of capital. The reason is that the gum of mint stamps, and this is especially true of NH stamps, requires an additional level of care and expertise when storing and when sold. The question of regumming, raised at time of purchase, will always be raised again at time of sale whether the stamps are certified or not. And even under the best of conditions, gum can deteriorate and perfect gum may not be so when you go to sell it. Fine quality used stamps require no care and, if toned or foxed from faulty storage, can be restored to original condition with soaking. We have seen many "investment portfolios" ruined because the gum was damaged by poor storage. If you are putting stamps away for the next generation consider protecting yourself and your heirs by buying used stamps.