The FX1 is one really old camera, & other than it being cheap used there probably isn't a good reason to get one.
The second question you need to ask yourself & answer, is how do you want to use the camera. FX1 is tape based, every new camera today shoots on flash memory. Pros & cons for each.
But the first question, is what camera will make you money. Many clients don't care what you use as long as it looks good, but other clients will want Model XYZ or bust.
Search the freelance forum for old forms about starting to freelance & good cameras to purchase.
I've personally used the FX1 a bit & the Z1U a whole bunch back in 2007-08. I think they're pretty good cameras overall. I've seen two FX1 cameras die b/c of some internal power failure & for that reason I'd stick to a Z1U, that & I want my camera to have XLR inputs, BeackTek adapters (or whatever) are nice, but not really as user friendly.