All of the "modern" Ducs are pretty good, they're all based on the belt driven cam model "Pantah" engines that saved Ducati from the scrap bin of history, their predecessors, the "Bevel" twins, although all awfully collectable nowadays, were poorly engineered pieces of sh1t that had probably the worst build quality of any bike, apart from those made in Eastern Europe, back in the day. I know, I owned a 1979 900SS, and as beautiful as it was, it was rubbish.
I love the Monsters though, and especially the DOHC models. I narrowly missed out on a S4RS 4 years ago, and once I "cull the herd" somewhat, I'll look for another one. My son was very interested in the little 400 Monster a year or so ago, but the problem that we had was that the ones that were available had questionable service histories.
A point that didn't escape me when I spoke to a friend who's into Ducs was that yes, while you can do most of the maint on a modern Duc yourself, if you don't have a service history from a recognised Ducati dealership here (and probably in "Un Zud" too) you'll never sell your bike for anything like high retail, because people are still suspicious of Ducati's legendary poor reliability, even if the modern bikes don't deserve to be lumped in with the old bevels. Cheers, Terry.