EXX.com exchange have $98,921,809 USD (13,371 BTC) trading volume. I think they are legit. But don't be fooled by the huge difference in margin, the 121 USD showing may only be a sell order made by someone. It does not necessarily mean you can sell at 121 USD
I agree, often such bugs are very common.
As for the exchange itself, I liked it very much, you can trade on it, but there are shortcomings in the interface and for me as for active trading it is not suitable
