Hi, we bought a timeshare after swearing we never would. Why? Well, put simply it was (to us) a pretty good offer. The accomodation is great (http://www.angrypig.com/belize/
for some pics of the rooms) and we bought 2 weeks every other year.
This means we are not tied to AC every year but we do not have the hassle of selling the weeks etc. The system they have for selling / swapping sounds good but it still ties you to places with time shares which we may not want.
So, it's not the cheapest deal but if you compare to a reasonable hotel - we stayed at Ramons, it's pretty good. So far they have been very friendly and helpful.
As for the resale market. Agreed, if you can get it cheaper then why not. BUT...Belize is a very small and desireable market. In Florida the resale market is fantastic as it is so overcrowded. In Belize I don't think that will happen. Treat it as a vacation reservation not an investment and you won't go too far wrong.
Oh, and labour with an 'extra' u is labouur and that is just silly!!