Hey Ian,
Yep, you pegged it. As with so many woods, different common names. Imbuia is a wood that once discovered in SA, has been imported to Europe since. It's a wonderful wood. Works like Walnut, though it seems denser it isn't really.
Favorites? That would be a moving target. I love wood. Some slabs have sat for years in my attic in anticipation of using them one day. So when someone selects one of those timbers, I so excited to use it, to discover how this piece or that needs to be shaped, I overlook certain workability issues compared to another species.
In retrospect, the most consistently enjoyable has been the red and black Cocobolo I made Phil's saw from. A few years ago I bought three planks, 2" thick x ~7" wide and 4' long. I had intended on reserving one of them. I cut into it two days ago.
But close on the heels is this Imbuia or Black Walnut. Probably one of the best handle woods is Bubinga. Eddie of Adria choose a wonderful wood to use and I feel good to follow his lead. And besides, I have some wonderful slabs of figured Bubinga to cut into :lol:
Jatoba makes for a great handle wood. And Sheoak. Derek made me a marking knife using it for the handle. Cannot wait to make a saw handle from some.
I have a series of 35 saws going to be made using Macassar Ebony. Probably start on them after the first of the year. We'll make the 35 and that will be that for that series. The next year, another wood, another series. While I haven't used M. Ebony for handles, it is plenty strong without being brittle and carves well--something we need to do with these.
Probably didn't answer your question well. So many woods make good handle wood and all have something unique about them. I love wood.
Take care, Mike