Pete, I will give you my experiences with those cuttings. I have successfully rooted all 3. Others will have different results than me.
BM - not difficult to root, just took longer to root.
BI - not difficult to root
Calvert - not difficult to root
Both BM and Calvert need a long summer season, we have that here in the Carolinas. :) My source for BI like most is UCD. Their tree is infested with the mosaic virus but is is growing well there. So, for BI, it really depends on the cuttings. My cuttings rooted just like the past 2 years but later died after a few leaves. This year, I got 2 that rooted fine and they LOOK strong but now comes the tough part. In the past 2 years, I did not have much root mass with I repotted my BI cuttings. THis year, I did 2 things different. 1. I used peat pots to root them. 2. I used self watering pots.
My 2 BI have been in the shade every since they rooted and leafed out and guess what, some of the leaves look like they are sun burned even though they never had sunlight. GO FIGURE! But if they don't make it, at least I have my in ground Smith. I like this tree and so happy to see it grow and produce some awesome figs!