JT9 certainly gets you to most places on the globe with low power and poor QTH/antenna. Choice of band to use depends not only on propagation, but also on restrictions we have to live with, imposed by the different IARU bandplans according to region. It seems to make little sense to me that for such world-wide usage IARU has different rules by region.
For example, in 30 meter band (10.100 - 10.150 MHz) allocated by ITU for radio amateurs as secondary users, the IARU in region 1 restricts digital modes to use only 10.140MHz to 10.150MHz. Region 2 and region 3 have different rules! JT65A (10.138 MHz) and JT9 (10.130 MHz) Region 1 users beware! Today there seems no logical reason for this anomaly. Maybe eventually the IARU will realise that modern amateur radio communication actually does work between stations in different regions working on the same frequencies. They surely need to harmonise their bandplans in order to retain some credibility. Here's hoping!