I would guess that the majority of chips sold on E-bay are uder $15.If you can get to the carribean on that, have at it.
I doubt that anyone would spend months if not years to accumulate a good feedback rating to bilk someone out of $15.
I personally view the feedback of everyone i'm about to do business with. Although its not a clear indicator it will certainly give you some insight.
Would you send in payment ot someone who has a history of negative feed?