Hi there,
One is not categorically 'better' than the other. It all depends on your particular lifestyle, the people and/or cargo that you need to carry or have access to, and what works best for those people or cargo. One advantage of the bench is more seating capacity; one drawback is that it's a bit more work for passengers to gain access to third row.
I have the captain chairs in mine and love the setup. Passengers feel like they've got their own real estate back there---and it's simple & quick for passengers to walk between for the third row.
What seats do you have in your Tahoe now, and what do you like or dislike about it?