I found it easy to install. You will need to bung or drain the system first if vented. I drained, to get out the loose stuff. If your system is already full of expensive inhibitor, I would bung it before draining into buckets so the liquid can be re-used.
One thing I would do differently:
I followed the instructions for cutting out a length of 22mm pipe (they say what length, 133mm I think it was).
In my case, the lower pipe then dropped a bit under its own weight, and when tightening the two compression fittings, I hadn't got enough hands to lift the lower pipe tightly into position, while holding the Magnaclean body with my other hand, and the spanner in my other other hand.
If doing it again,I would cut the gap a bit smaller so that it was naturally pressed tightly into the fittings. You should be able to see how much the pipe drops after making the first cut.
Also, the stubs on the body are off-set, so that the body will lie diagonally (if using existing vertical pipe). The nearer to vertical you can fit the body, the less likely it is to spill water when you take the top off. You can twist it a bit while tightening up, if you have some play in the pipes.
I intend to fit some more pipe clamps to resist the torque of the spanner when removing the top to clean off the magnet.
BTW, in my own house, I intend to use DS40 shortly which I hope will remove old lime scale (very hard water area) to stop my iron Flamingo bonking (as recommended by Tony on another thread). My own system seems free of black oxide.
