But they do believe that theirs is the prophet and religion for another 800 years or so.
At least that's what Bahais have told me.
Frankly, while I consider their Messengers quite sophisticated for the 19th century, they've been surpassed already in terms of moral and theological sophistication. The human world is changing a lot faster than they(or God) realized it would.
For all Bahai folks know, God may have already sent a new Messenger for the 21st century. But your Messenger made a different claim so Bahais will either miss him/her, or treat them like the Bahai Messenger was treated.
Tom
There would be some intervals between the God's revelations, because, the teachings in each revelation are designed to be suitable for a certain period of time.
Now, ofcourse if we were to consider the opinions of people about teachings of a religion, they would certainly have different opinions about those teachings. Some may see the teachings infallible, while some will see some of them invalid.
But, discussing this more at a high level, the Bahais don't believe there is an end, in God's revelations. But that does not mean, God will send a new Messenger every day, or every week. The period between Revelations has been centuries, which makes sense, since it really takes centuries for people to forget the message, or misinterpret them significantly, or the new age requirement, makes the religious laws inappropriate.