RCI and inability to provide international exchange Units

It would appear that RCI are not as good as they promote and that Time Share is nothing more than a money spinner for companies like RCI. Although we own no less than two six sleeper timeshare units in South Africa, whenever we query or attempt an exchange internationally (Europe, six months ahead) we are either offered studio's or 1 & 2 Bedroomed units or informed that there is nothing available. The last two attempts at attaining an international exchange resulted in us having to eventually pay for accommodation in Europe and shelve any further attempts of timeshare, due to there being nothing available. This must beg the questions as to, is the system over subscribed, or what is resulting in units not being available despite the influx of Europeans we see to the time share units here in S.A. Are these Weeks being sold to non RCI Members. The very essence of Time Share and associated exchange is that there would always be sufficient for the members. The only way a shortage occurs is when the weeks are being sold to non members at a fee that RCI or other such time share companies benefit from and not the owners. Unfortunately the only way to bring this issue back into line is not to bank your weeks and if you cannot take the holiday at your actual units then let them lapse. This way RCI will be forced to afford their membership priority and not sell off the weeks to the public or non-members. I have taken this issue up with RCI however, until the membership takes a stand and takes back ownership of the scheme this will debacle will continue. I'm sure we are not the only family that has been subjected to this type of issue however, I believe it is important to ensure the public are aware of this issue and that those who are considering Time share are informed of the present issues and disappointing experiences they can look forward to.