I used both for a while. I loved the ease of MOH. I didn't do all the activities, though. I think for a newer homeschooler it is such a blessing.
But having tasted of the rich discussions and great stories while doing Truthquest, I did notice that after a while, the MOH readings though full of facts were not inspiring after a while. The kids would ask me, what do you want us to know from here. Their eyes did start to glaze over. So, once we hit the Egyptians and could incorporate the TQ guides, we left MOH though occasionally referring to it for extra information.
TQ does have a learning curve. It took me a while to figure out how to use it in a way that works for me. We use one spine (the H.A. Guerber books) and may incorporate some of the G.A. Henty audio (Cat of Bubastes is GREAT!!!), and some historical fiction cited in the guide for read aloud and independent reading and follow the guide. I do not attempt to use every book. But what we do use is living and inspiring.
So, this is my experience. There is some information that only MOH offers, but for my children it was not relayed in a very living, inspiring way. But it is extremely easy to use for the mom. Now that MOH comes in audio form, you might be able to do both MOH and TQ, also. MOH does start with creation whereas TQ begins with Egypt. This is because the author of TQ did not feel a need to rephrase or re-do the Book of Books! But we did learn alot about this time period through MOH that I do appreciate.
If you check the archives here you will find some older discussions of this very same topic, as well.
Hope this helps!