The 518s are a fairly simple
fixture. Just a scanner like the MX1, not a multi-beam/breakup
roller like the
Wizard.
The 518s do not have remote focus, so you will need to adjust the
lens by screwing it in or out at the
fixture. This usually isn't an issue as there's only one
gobo wheel and there's a
frost filter on the effects flag if you need it. I think this focusing is how the MX1s work if I remember right.
The 518s have a bunch of colors, all in rainbow order, with 2 quad colors on the end to split things up. They have 5 rotating gobos, which are disgustingly hard to change, but it's worth it to get a
bit more
image area if you're going to be using these fixtures a lot. Get a breakup or two and maybe a good
dichroic gobo for the fixtures if you're going to use them for a lot of shows.
They are a discharge lamp - so they will surpass the MX1 output-wise no problem. You need to make sure that you have the upgraded
fan in your
unit if you're going to be using an MSD250 lamp, the fixtures were originally designed for an MSD200 and then after a certain serial number the new fan was installed at the factory. It is an upgrade that can be performed on the older units to allow the use of an MSD250 lamp, which will get you a good
bit more output from the
fixture.