The main problem in fitting this Spaziale steam arm is that the attachment nut is much shorter than the Faema/Cimbali one. The nut is of the same thread, but since it is shorter the nut will not go on with the standard spring inside it. If installing the arm without that spring, you risk damaging the gasket that sits against the ball-joint, as the gasket is pressed against the body of the steam valve as itís tightned. The arm is also too loose without that spring providing pressure on the ball-joint. Itís a bit difficult to explain on here in words, but it just seemed like a bit of a dodgy fitment to me, and I wasnít satisfied with that.
See photo below for comparison of Faema E98 steam arm next to the Spaziale S5 steam arm: