The L2 with airspeed engaged is fine if treated gently when making changes to either altitude or speed (ARAs require a little more care than the 225). It doesn't like high speeds though and it will quite happily pull above max continuous if airspeed is beeped up to higher speeds. This is often catches out ex 225 drivers when ATC ask for an acceleration from say a holding speed of 110 with IAS engaged up to say 140 - it will generally then pull above max continuous to attain the speed if, only briefly, which is why it isn't used for faster precision approaches. We fly all our NPAs four axis though using the method described above i.e. with an Alt Aquire and adjust VS for the profile.