I have always used the Alko, however changing my can this week to a longer one doesnt give me enough tolerance on the drive to mess around with the Alko, and I too have gone for the Nemesis. Incredibly easy to fit and seems almost as secure as the Alko. Combined with an Alko hitchlock I have no security worries.
The Nemesis is well packaged, seems robust and secure. It takes a few minutes extra to initially setup, but once done it has made my life so much easier.
I am also intending to add locks to the steadies for when the caravan is on my drive.