This Ducati valve thing is one of the most over-rated maintenance tasks in motorcycling. It must be one of the salesperson talking points that they teach at BMW, Honda, etc
One of my best friends and riding buddies has two Ducs with Desmoquattro (4 valve) engines, he does all his own service... those things are a bit more pain in the ass but having assisted on those I'd have no qualms about doing a nice simple two valve Duc myself.
On a naked bike like a Monster or Multistrada it'd probably take me 6 hours the first time I touched the bike, 2-3 hours after that. Notice that Ducati does a nice job of enginnering the access you need to the heads... removal of gas tank, fairings, etc.
P.S. The service interval may be 5,000 miles but when you check the tolerances it's unlikely that more than a couple valves will be out of spec
Although I have not done a Duc valve check yet I do plan on doing the valves on my Multistrada.I think because they have an opening rocker and a closing rocker people think they are more complicated,but I think a little more time consuming would be more accurate. I think removing the bodywork and just getting to the valves can be very time consuming on any machine.My old 16 valve Suzuki was very tedious to check valves on also.
I've never done a 4 valve engine, but I have a Monster 900 and I've always done my valves. It's a lot easier than otherwise claimed by those who want your money. Follow the instructions on ducatisuite.com as a guideline and get the right tools, a micrometer is a must. Get a set of collets from Martin Brickwood (www.mbp.com) he can hook you up with a measument tool for the closing shim. It's a bit intimidating at first, but get everything in a advance plan what you are going to do and get to work!!!
ps: It's very satisfying to fire it up after the valve job is done and know that this is your work!!
Desmo valves are not hard to adjust. I would rather do the valves on a two/three valve ducati than many of the four valve Japanese bikes. Other MOrons have posted some good links.
The only problem that you might have is that some dealers are reluctant to say your warranty will still be in effect if you do your own adjustments. Some don't care. Some will say that your warranty is OK as long as the fault can't be traced to out of spec valves.
But don't let the dealers put you off with horror stories, especially those told by dealers of other motorcycles.
I have almost 15000 miles on my '02 ST4s. In that time, only one valve needed a shim change. Checking the clearances is no more difficult than any other engine type. Get the right tools up front, buy the factory manual, read those websites, and work carefully. Each time it gets easier and faster.