yes, Traders is 4star hotel. however,so far i noticed that the feedback for some 5star hotel might not be better than 4star hotel (e.g.plaza, carlton), in term of their service and food. so think it is subject to individual preference also.
As for the pricing, the price for traders has increased next year. For weekday, it is close to $800 after +++, but has included free flow beer and wavier of wine corkage.