The user experience is quite bad, IMO. Even if the 0.6.1 wallet is way better, there are many annoying things. If your short is fractioned in 10 different transactions, you'll have to cover each of them manually, paying a fee for each. When one asks for a price by clicking on it, a slightly higher price is selected. You ask for 1000, you get 999.999. On my Mac, scrolling down is very buggy. Clicking on a button doesn't exactly feel like it should feel, for example the "confirming" action after putting an order should be a pop-up like thing rather than appearing where it does (and it can be easily missed). Graphs are erratic.
We need to have some user experience expert asking traders what they would need to really use the exchange.