Oh, and I've had more than 300 transactions on Bitmit by myself, so the total number is a lot higher than that. If you add together the feedback scores of all the sellers you listed, and added something like 50%, I think that would give you a more correct idea about the number of transactions. If you were a Bitmit user, you could also look at the internal order numbers.
Did that. The total amount of feedback is probably around 1400-1500. I am looking at positive feedback numbers, so I'm getting an approximation. If you've sold 300ish items, that means that your seller feedback represents about 2/3 of what you've sold since you ahve abotu 200 pieces of user feedback. So if that's the case, and that's consistent accross users, that means that this analysis is abotu 50% off, which still puts the total number of transactions on the site at between 450 and 1050, which is a big range and a higher number, but still a tiny number of transactions that have been facilitated.
How did you come up with the numbers 450-1050? Like I said, I have personally made more than 300 transactions. "Steamgames" has a feedback score of 400, so between the two of us that's at least 700 (and more probable, 900) transactions. If you just added together the feedback scores like you say you did, you should get a total feedback number around 1000 for sellers. Add 50% to that since not all buyers give feedback, and you have a total number of 1500 transactions.