One thing to note on this system. The magnets do start to lose their effectiveness after a few years. I think that can be avoided somewhat if the magnets are stored on a metal plate with the same side down or something like that. Honestly I don't know how it works, but I did read something somewhere that explained why magnets lose their pull and how to avoid it.

I use so many magnets with my system that it's not worth the trouble of figuring out which end is up. I bought 500 magnets earlier this summer to replace mine and just bought another 500 for fixtures that I build for folks.

It is an excellent system. I've been using it for about 5 years now and still love it.

BTW - the magnets from the magnet source are the exact same as the ones in the GP system. The difference is that GP charges a lot more for them.