The best and most reliable Geese are fuel injected V1100 series of Basa, Stone, Jackal, EV and all the Sport series. Fairljy generic fi system without o2 or any feedback closed loop nonsense. Simple pushrod valve adjustment every 10k and oil changes as needed and you are done for the year. The only goofy thing is the oil filter inside the oil pan that gets changed every 10k miles. As far as parts goes, fi parts are generic webber and can be had from MG or your local Harley dealer or autoparts emporium.
Ive got 6 Guzzi V11s in the stable with a Duacti MTS1000ds and BMW R1200 GSA. Guzzi dealer since 1987 now retired.