I don't know what you have been sold but if you are paying for it as you go and if you are NOT locked into a long-term commitment, whereby you are committed to pay a fee per year for upteen years, than that sounds promising. There have been major problems at Sunterra Europe, including tax evasion on a grand scale. There are also loads of unhappy owners in Sunterra resorts who can't get out of their contracts and can't get the holidays they want either. There are various court cases going on. I am a timeshare owner (but not Sunterra) and I follow the industry quite closely. There is massive oversupply or timeshare in Europe, particularly at the low quality end and many people have been pursuaded to buy points to uplift their trading power. The big lie about this is that the supply has to be there to meet the demand and if lots of people believe they have 'bought' a better holiday by acquiring points there are more people chasing the smaller number of better quality resorts. That's why the model just doesn't work.
You may be able to make it work for you - I can still (but its much harder) - but just don't buy into a long term commitment. HTH.