Did the United Kingdom benefit or lose from its colonial empire?

I am currently reading Jeremy Paxman's "Empire" which is a great book that documents the whole history of the British Empire. I am currently reading the chapter regarding the Opium Wars with China. I have read several books on British history previously and I am familiar with the very telling quote from the head of the East India Trading Company: "Our glory was built on the wrongs of our conquests, for the one man to whom the whole nation is indebted for these great advantages was at the same time the cause of more misery to the human race than any one person ever was."<br><br>I am of the opinion that much like slavery, colonialism is a net negative and a massively immoral and shameful part of history.