"The book which I like very much is this"
Translation:Kitabu ambacho ninakipenda sana ni hiki
It certainly looks correct to me (though I am not a native speaker). I have always thought of the amba- relative and the relative "infix" as being equivalent, except there are some places the "infix" does not work, such as with conditional tenses: Mtu ambaye ukimwona utacheka; mtu ambaye (kama) ungemwona ungecheka; mtu ambaye (kama) ungalimwona, ungalicheka. And sometimes the amba- relative helps to clarify complicated sentences. And there probably other cases that don't come to mind at the moment where the amba- relative is required or preferred.