Do Airbus avionics give good deadstick landing outcomes?
Airbus (A320+) normal flight law will, at slow speed¹, maintain angle of attack according to the side-stick position, where full aft deflection gets you to the onset of stall.

However the ram air turbine (at least on A320-family; not sure about A330) does not provide enough power to keep all units on and then the system degrades to direct law, in which the side-sticks just control the deflection of the control surfaces directly. This is similar to any other aircraft except since there is no force feedback the side-stick does not become stiffer with increasing speed.

In the US-1549 flight case (landing on Hudson), they had enough time to start the APU, so all systems were powered and they had normal law and did take advantage of it to let the airplane settle as slow as possible.

In the recent U6-178 flight case we don't yet have enough information whether they did have normal law available.



¹ Slower than normal approach speed. At normal speeds, the system maintains wing loading at 1G with neutral side-stick, which can be also described as trimming for current speed. Until the trimmed angle of attack exceeds alpha-limit (12.8° IIRC; 17° is onset of stall, on normal approach should be around half of that), when it switches to maintaining angle of attack.