How is the price calculated on your site? If they are half price on hitBTC seems like a no brainer to purchase them.
The site price is the buyback price, which is calculated via the following:
Token Price = (Initial Funds Raised) / 70,000,000 + (Site Profit) / 100,000,000
The difference between the site and hitBTC is that one can dump all their coins on hitBTC, whereas the site has buyback periods in which you resell up to 10% of your on-site BKB tokens.
The first buyback period begins Dec 4, so if you want to sell your tokens, you want to have them deposited into the site before then.