Hello everyone, first post here.
Went out and tried this lens yesterday. Not on my A7 sadly but I used the A7II from the showroom. Here are my thoughts:
-AF motor is not noisy. Yes it has some noise but come on, have you ever used a Canon EF 35/2 or the EF 50/1.8 I?. I found the noise absolutely negligable.
-Focus speed, on the other hand, is downright awful. All my old screw driven Minolta AF lenses are faster. Also, the camera focused AFTER it made the AF confirmation beep, which is quite odd. If you listen to the beep, the lens is slow. If you wait for it to actually focus, it is even slower. I'm willing to pay double for the 55/1.8 just because of the AF behavior.
Something that I've also heard about was the behavior of aperture blades. I tested that too:
-When Setting Effect Preview is ON, the lens is always set to the set aperture. This slows down the AF speed even more if you want to shoot something stopped down. Also, if you want to use the MF or DMF mode, it's pretty hard to nail the focus as the lens is stopped down. Very annoying.
-When Setting Effect Preview is OFF, lens sets the aperture to a random value (Not the shooting aperture). When it's dim, it's wide open. When it's lit well, it's stopped down. When you half press the shutter, however, aperture moves to the shooting aperture after locking the focus. As a result, if you are outside during day, you're composing and focusing through a stopped down lens, only to see the wide open preview after you half press. Pretty silly, if you ask me.
I have found no way to keep the aperture open all the time. I've tested the same procedure with the 55/1.8 and it behaved exactly the same. Camera was a A7II and I believe it had the latest firmware as it was a showroom camera (They don't sell cameras there, they are just for people to try out).
I've been using A-Mount lenses on my A7 until now so all these behaviors are pretty annoying and pointless from my point of view. The trouble is, some of the most used focal lengths on A-Mount are rather weak unless you go big and expensive (24-50-85-135mm). Minolta 24/2.8 is rather acceptable, Sony 50/1.4 is absolutely nothing special and Minolta 135/2.8 is just a regret. Sony 85/2.8 and my Minolta 200/2.8 APO HS G are some of the best lenses ever made by anyone though and they are the main reason I'm in camp Sony.
I'm having very mixed feelings about going native into the FE mount. FE 55/1.8 is a gem, 28/2 is absolutely acceptable (although not my focal length), 16-35/4 is probably the best of its kind all things concerned but that's about it. I don't want to shell out all that money for the Batis and Loxia as I can buy into the Fuji system for half the money and take the exact same photos. Some focal lengths don't even exist yet (135mm, anyone?). This 50/1.8 did nothing to raise my hopes in my future in the FE system.