Still, I'd like to know what the price was at Mt.Gox. at the exact time that the exchange rate was set, so that I can compare them.
Instawire offers no such feature, there are no plans to implement it. That's how we roll.
I wasn't looking for a feature, I just thought that you could tell me roughly what exchange fee you charge your customers. I can figure it out myself by observing your price changes and what the price is on markets such as Mt.Gox. at that time, I just thought that maybe you could save me the trouble.