Having toured with a full suspension before (a BMC 4 Stroke) equipped with Old Man Mountain racks (they are the foremost authority in racks for full suspension bikes), I can attest that it can be done and be done reliably. In fact, my former BMC 4 stroke bike WAS LIGHTER than a Surly LHT or even LIGHTER than a Raleigh Sojourn. Of course then, it was a bit more expensive but the bike itself can hold its own in terms of speed and agility. The only plus side is when I go off-road and my friends with conventional touring bikes just can not keep up with me. Plus they complain about the discomfort on the hands and spine, whereas I have very little in terms of discomfort.

In terms of reliability, modern suspension bikes are extremely reliable. People ride fully suspended motorcycles on tours too, so why not with a bike? Plus the newer suspended bike rides like a hardtail and only engages when you hit a bump. Gone are the days of the URT design like the Trek Y bike or the GT iDrive which is an improvement but a major pain in the neck in terms of reliable. I toured with a GT iDrive and I would not recommend it. But with modern bikes, choose a bike that fits your budget.

After the lost of my BMC 4 stroke off-road bike, I recently bought a 29er hard tail bike and am planning to use it to tour next year. The advantage of the 29er bike is speed and because of the larger wheels, the ride is much smoother than a 26" full suspended bike until I hit some major bumps. But then, I can add a Thudbuster ST suspended seatpost to smooth those bumps. 29er bike is the best of both worlds in terms touring in North America, whereas 26" MTB is best for outside North America tours.

There are many cyclist tourists who TOUR with a fully suspended bike with racks or towing a trailer.