There are many different seam guides out there - I also have another Singer one with a plastic piece under the guide that the screw goes through before screwing into the screw hole on the bed/needle plate. This was supposed to stop any damage to the finish on the older machines - though I still prefer the original I sent a link to.
The link you provided Cas shows yet another version of basically the same thing and there is also a Singer version like that. I also have a similar one on my German Vesta machines.
I don't like the idea of a magnetic seam guide on computerised machines, or those with a magnet in the bobbin mechanism. I guess they are ok as many people use them, but I'm going to be cautious on that one. I would use them on other types of machines - if I had a decent one! If you like the magnet ones and are happy to use then there are lots of different ones of those out there too
including some wonderful ones from Sailrite, though the magnets they use are very strong so they won't move when sewing heavy canvas on their industrial type machines - I wouldn't put those anywhere near my computer let alone my computerised sewing machines!
My philosopy is not to be blinkered into buying things just because they say Janome on them,
and to try other things I may already have first that may even work better. I also will try things that others have said do not work - though of course always being cautious to ensure I will not break anything! I feel unless I tried them to see if there are issues that I could resolve, I would never know if it was something really simple and I might find something that was brilliant for my own use.
Just my thoughts! :0)
Anne
www.sewingtales.wordpress.com https://www.flickr.com/photos/94302460@N03/sets/ "Live like someone left the gate open". Kimberly Burnham