i've beenplaying round with the rare earth magnets in a similar configuration to Karhedrons pic, i've used 2 more magnets so my configuration looks like this
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i've not really had much joy with the whole setup really, still cant get a reliable/consitant uncouple to take place. If you move the trip pin too close to the center line then the opposite row of magnets tends to grab it, ie the right hand magnets grab the left hand sides pin. I might just have to change the configuration to 2 rows of 4 with no offsets. i'm using 3mm dia by 2mm thick Neodymium, 50 of them for £9
I'd still like to know what the height of the trip pin should be in relation to the rail head. too low and you foul the frogs of points or the magnets grab pin and nose down the coupling altogether. Too high and nowt happens!
The Dapol magnets are ok and do the job just about (but not looking forward to chopping out all the ballast and sleepers to use them if it comes to it), but even then you still have to faff about with centerline alignments and heights.
As for the shunting with them on either magnetic setup, i cant manage more than an inch or two before they couple back up, probably my ropey track work i expect.
Even after saying all this, they're still better than rapido's and the hand of god, (or in my layouts case it would seem, paw/arse of cat!!!)
one other thing i did have a little succes with was bridging the little magnets in each row with a peco track pin, seems to help spread out the magnetic field over the sleepers.