It's considered one of the best woods to use because it's dense enough to sink on it's own - no weighing it down with rocks/magnets, etc.
For some species (mainly certain plecos to my understanding) wood is a required part of the diet, so it's helpful for certain fish to include it in their tank.
As wood decays in a tank, it may leach tannins that will discolor the water and add a brown/tan tint to it. This can be rectified by water changes to reduce the discoloration.
Also, as it decays it'll drive the pH lower - good for some species and not for others. For african cichlids you typically don't want this so I would suggest using it minimally, if at all. Of course water changes can also help combat this by removing a certain amount of the lower pH water and replacing it with your higher pH water source.
