I have an f250 with the v10. Engine is very durable. Biggest issues that come up are spark plugs and oil consumption. The biggest issue for most people is the fuel economy: 9-10 around town, 13-14 highway if you keep the speed down.
From what I've read they are good engines just thirsty. Look at RV's, alot of the smaller ones run the ford v10. RV manufacurers wouldn't chose it if it wasn't a solid performer.
The V10 engines are very durable. The Excursion suspension never had much travel from the factory and generally suffer from spring sagging that makes the travel issue worse. Spring wrap is also an issue in stock trim. Spring swaps however are easy.
In mid year 2000 Ford switched over to an modified head design on the V10 (commonly called PI heads) that increased the number of spark plug threads and pretty much eliminated the the spark plug issue. You still need to be careful about over-torquing the plugs during replacement.