If a person doesn't believe in gravity, the common response is "then go jump off a cliff". It's a simple challenge. If they won't jump off the cliff, they're acknowledging gravity, but if they do attempt to jump off the cliff, they'll soon see that they should have believed in gravity.
In like manner, Muhammad's response to those who disbelieve in the Qur'an is "then bring a Surah like it, and call on a witness besides Allah". As a gravity denier is supposed to either confess they can't jump, or attempt to jump and be proven wrong, so also is a Qur'an denier supposed to admit they either can't produce a Surah like it, or try and fail.
This challenge has been met multiple times in history, most recently by a book called the True Furqan. The True Furqan mimics the Qur'an in a more Christian context. It does such a good job that when the authors read it aloud on a train, some Muslims responded by thanking them for reciting the Qur'an.
In Christianity, there are a number of arguments which have been made in defence of the faith only to later (or even very quickly) be refuted. Laminin, for example, was once used as proof that the Bible is true because it takes the form of a cross. Not only is this argument clearly very silly, but it turns out laminin doesn't always take this form, it just sometimes vaguely resembles it. But however many arguments for Christianity are sent to the intellectual graveyard, exactly zero refuted arguments actually come from the Bible itself. The Bible doesn't say laminin takes the shape of a cross, and so therefore you should become a Christian. But the Qur'an does say that men and jinn combined cannot produce the like of the Qur'an (Qur'an 17:88). If the Qur'an says man and Jinn can't bring a Surah like the Qur'an, but Al Saffee and Al Mahdee managed to bring 77 Surahs that resemble the Qur'an closely enough that Muslims can't tell the difference until they try, the inescapable conclusion is that these parts of the Qur'an are false.
But we'd expect far better from an infinite intellect! The central argument of the Bible is the miraculous resurrection of Jesus, who appeared, after His crucifixion, to 500 people at once! The only way people get around this argument is to raise their skeptometers so high that to apply their arguments consistently, they would have to say every historical event prior to 1816 is a complete forgery. But the argument Allah uses falls flat in as short a time as it takes to write a book, hop on a train, and read it out loud.
It's clear from this example that God is vastly superior to Allah. Given the choice between an idol whose main argument is silly to begin with and is easy to refute, and a God who verifies His claims by splitting oceans, burning up drenched altars, healing the sick, feeding the hungry and successfully predicting His own death and resurrection, I'm going to have to pick Jesus every time.