If your cannot accept the possibility of angelic visitation, then your attitude towards Mary, whom some Christians said was the Mother of god, would be questioned?
So, because I can discern true from false, you think I am incapable of seeing the truth? Interesting perspective.
If you want me to be blunt, rather than working it out for yourself, as I hoped you might, then I will.
From the point of view of mainstream Christainity, Mohammed is
not a prophet. Not to Christians, or to the world, and possibly not at all. The best we can ever say (and not every Christian would say even this much) is that Mohammed is a prophet, of a kind, to the arabs, and then by extension to his own followers, and his faith is a distinctly arab one; a primitive mishmash deriving from Hindu, Jewish and Christian elements. He has nothing whatever to say to mainstream Judaism, to mainstream Christianity, nor even to those of a humanitarian focus wanting to find leaders of credibility, great morality and humanity, such as for example Gandhi. Gandhi gets a very high 9.5/10 from me, perhaps more. Mohammed would not score beyond 2 (although some of his followers would score far higher, in my view). Buddha, 8. Christ, 10.
This is exactly paralelled in Judaism. Christians claim Christ as a the Son of David and the Son of God. We say he is in the direct line of descent from Abraham. Jews on the other hand say he is nothing of the kind; he is not even a prophet.
To be honest, as a Christian I have a lot more sympathy for the Jewish position, that their Messiah is still awaited, than with the Moslem one, which is that our whole faith has to be denied, and Christ reduced to the level of a prophet, in order to receive honour. That kind of honour is no honour at all.
I do not find the message of the Koran convincing, not least because of the lifestyle and example of the man who composed it. And there I will draw a line, because I do not think any purpose is served in spelling out exactly why this is.
The angel Gabriel appeared to Mary, and announced to her that she would bear a Son who would be the Son of God, conceived by the Holy Spirit.
Whoever and whatever appeared to Mohammed did not have the knowledge of our faith that would necessarily follow from an angelic visitation and therefore his whole message is called into question; the evidence quite simply is against it, in the same way as the evidence for the 'angelic' message to Joseph Smith about the ancient Egyptians travelling to America and becoming the native Americans is called into question by this assertion being complete gibberish.
None of this prevents people from believing either, if they choose to do so. But it does prevent informed people of other faiths being able to suspend disbelief enough to be fooled in the same way.