Today I went back to using my 8x10 camera for test shots of this still life series I'm starting to work on. I'm trying X-ray film, mainly because it is more affordable than "real" B&W 8x10 film, and because I have a box on hand.
X-ray film is a bit fussy. It scratches if you look at it the wrong way. You'll get finger prints all over it if you don't wear gloves when handling it. You need to pre-soak it before developing or it may end up with uneven developing and look like crap. And it is best to tank develop it using hangers as opposed to tray developing it which will scratch the hell out of it.
Fussiness aside, the film is very affordable. Kodak Carestream 8x10 Green X-ray film is about $39 for 100 sheets. Kodak Tri-X 8x10 is around $75 for 10 sheets (yes, 10 sheets, not 100). So if you can't afford to use Tri-X for testing, or even everyday photography, X-Ray film seems like a good choice.
I haven't compared them side-by-side yet, but I'm sure Tri-X is going to give you a much better negative. Tri-x is a panchromatic film which means it is sensitive to all visible colors of the spectrum. X-ray film is orthochromatic which is sensitive to all color except red. With X-ray film red in an image will display as black.
From my minimal tests I definitely think it is worth using as affordable option to "real" B&W 8x10 film.