On a few of the US forums, particularly 360tuna, they insist that the JB 60 hollow breaks at about 90lb, but if you look here;
Paulus Just Fishing: line testing you can see JB 60lb hollow broke @ 50lb, & 130lb hollow broke at 96lb, EEK!!!
I had a couple samples of JB sent to me by the fantastic dealer Basil from
BHP Tackle, and I took a pic of the line v's some alternatives. A is daiwa boat braid PE4/55lb, B is JB60lb hollow, C is daiwa boat braid PE6/80lb & D is JB80 hollow. The pic doesn't really capture how nice and floppy it is, it would pack down very well. Another oddity is that JB100lb may actually be thinner than 80, because of the number of carriers.
I'm a bit interested in the fingercuff splicing etc, it looks like a really neat system and being able to splice in replacement line using a 100% join would also be rad. The two runs of 80lb hollow marked D is in fact a loop I put into the 80lb hollow using a latch needle for a bit of fun. IMHO you need a fairly nice needle for trying same in 60lb, its super fine.