But that wasn't your question..you asked if Lallana was better than we already had and he is! The fact he would strengthen the bench or even if we should buy him is irrelevant. He is better and it's absolutely essential that we strengthen the bench. When you can only call on Aspas, Alberto and the like they are not going to change a game in fairness. But if you could bring lallana or sterling or Henderson on after 60 mins then these are players who have the ability to make things happen.
I agree that lallana would probably cost too much and maybe suso could do a job ( although unproven whereas lallana has shown he can ) but you asked was he better than what we have and the answer is yes.