Apropos the above posts the final trade price is wrong, often way out, and anyone who thinks that Betfair will make any effort to fix it obviously is unaware of their abysmal track record. Betfair fixes stuff that isn't broke, thus breaking it, and then doesn't bother fixing the broken result.

Furthermore that final and current trade price is typically useless.

The correct figure that should be displayed alongside the current price is the weighted harmonic mean of matched bets.

This is easy to do, and is essentially what Betfair was proposing as their replacement for the offical SP.

However they show every sign of avoiding that obvious necessity. Presumably they are afraid that instantly being able to assess the true price will help inexperienced players, thus making it harder for the experienced well-informed sharks to rip the newcomers off.

My tip to newcomers is not to get sucked in by what appears to the current price but instead set your own price at what appears to be favourable to you. This means that sometimes your prices won't get matched, but the better prices you do sometimes get more than makes up for not getting set.