Either bike will work...personal preference.
But I stand by my opinion. Gravel riding rarely requires the grip offered by mtb tires. Plus that if you are not riding in sand the extra float won't be of use either. Some good seriously knobbly cx tires will give all the grip one needs on gravel. Leverage should rarely be a problem on gravel. At least I have never felt that I can't throw the bike around fast enough when encountered with loose sand on tight corners.
I like the variety of different 29er tire sizes...from big apple or nanoraptor 2.1 inch floaters to 28c road tires I put on in the summer when roads are more hardpack. I also believe a 29er makes a better snow bike...may or maybe not in the equation in this case.
Good to have choices and personal preference all said. If only two bikes, my personal preference is a road bike and the versatility of a rigid 29er...either single speed or 1 X 9.
"Obviously, I dont want or plan to take my road bike on gravel..."
Why? Bicycles are wonderfully versatile machines. Try it, you might be surprised.
The salient point is the nature of the gravel roads the OP wants to ride.
Some gravel gets packed so well into the dirt that normal road tires are fine. Some is so loose you want a MTB tire to float on it.
Riders at on the mixed course of the Strade Bianchi this year chose 25mm tubulars. I suspect the same would be true if the whole course were on the white roads. They're made of fairly fine aggregate and pack well.
If I, for example, were recommending a budget priced bike for those specific roads, I'd suggest an older steel frame with a modest new group, nice wheels and some nice 25-28s to go on them.
Last edited by Campag4life; 03-07-13 at 10:56 AM.
I also think the examples from IthaDan and garysol1 are really sweet.
Anyway, here is my bike after a ride on gravel with packed snow, ice and mud. No handling issues here.
Telemachus has, indeed, sneezed.