The quality of these seems fairly good to me. I had a couple of issues though.
Firstly the left side strut had the fixing sockets pointing in opposite directions. I expect you might be able to turn the arm until it faced the right way. My old ones can be turned but the new ones won't budge by hand so I unscrewed the fixing from the hatch end and used a washer to allow me to screw it back on facing the right way.
Secondly, after fixing both sides, I found the interior lights weren't switching off when the hatch closed. I figured the hatch strut was involved in turning the lights out but I didn't know how it worked. After a bit of internet research and going back to look at the strut it was pretty easy to sort.
The right side strut has a plastic collar round it, above the metal socket joint, where it attaches to the body. A wire attaches to this and inside there is a strip of metal that makes contact with the arm of the strut. At the other end of the arm, attached to the bottom of the gas cartridge, is a plastic piece that covers part of the metal arm. When the hatch is closed this plastic goes inside the collar bit and acts to stop the metal strip making contact with the arm. So there you have your switch. The wire attached to the collar is ground for the interior light, when it the metal touches the arm the light is on, when not it is off.
Turns out the plastic collar can be moved up and down. It was a bit too far down so the metal strip was always touching the arm. Move it up a bit and, hey presto, the lights now go out.
The hatch now goes up with the button and the key, hurray!! There doesn't seem to be too much force when it goes up either, as far as I can tell, so thumbs up so far.