My wife and I have been to Sir Winston's three or four times and we have always enjoyed the experience. We recently re-visited Sir Winston's and we were not disappointed. The Beef Wellington was very well done and we highly recommend you pre-order a souffle when you are seated.
The atmosphere is nice and quiet allowing for a pleasant dining experience. We try to avoid loud restaurants as we actually like to have conversation over dinner.
The cost is pricey but its really worth the cost once in a while to treat yourself to a great dinner with a great view of Long Beach.