An exchange's shadiness can only affect other exchanges in proportion to its market share. If there was price manipulation on Mt. Gox and it spilled over to all other exchanges then that was because Mt. Gox was the dominant platform for trading bitcoin.
FX in general is very difficult to regulate and there are a lot of shady firms and exchanges out there. However, I think it's hard to argue that the price isn't reflective of the true exchange rate. Over $5 trillion/day changes hands at a tight spread and very low volatility. Finance is based on trust and eventually legit venues get reinforced through a feedback loop.
FX in general is very difficult to regulate and there are a lot of shady firms and exchanges out there. However, I think it's hard to argue that the price isn't reflective of the true exchange rate. Over $5 trillion/day changes hands at a tight spread and very low volatility. Finance is based on trust and eventually legit venues get reinforced through a feedback loop.