If you're having derailment problems you may find that the switch blades don't make contact with the stock rails when you operate the switch to the diverging track, very gently bend the end of the blade that extra bit to make contact. As Kevin said, some are good, some not quite so. I don't have Aristo switches on my main line, only in the yard, LGB radius 5 are on the main and they are very good.
Cheers,
Kim
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