If they are in good shape and have carriers, get them. If there are lenses, even better!

If they are not all that nice and/or leave you needing to track down parts, I say pass. Better deals are out there.

If they are wobbly, rattly, unadjustably far out of level, dirty, missing condenser lenses or other parts, have raggedy bellows, or the movements are either too sloppy or too tight, and/or do not lock down, I would pass.