I'll agree with that for short runs, but RG-8X is only slightly larger in
diameter and less than half the loss per foot.

That's flat out factually inaccurate.

http://users.erols.com/rfc/attenrat.htm#RG8MINIX

The latter seems correct - this table indicates that the difference in
loss between the two at 10 MHz is only 0.1 dB, very small. I was,
however, under the general impression that RG-8X is somewhat more
durable...can't say where I heard that, however.

Bruce Jensen