If the walls is a rigid wall (reinforced concrete ot reinforced masonry) there is little difference since they are both cantilevers constructed on a concrete footing.
A segmental retaining wall (SRW) is a totally different animal since it cannot be on a rigid footing (compacted base instead) and is allowed to move slightly since cracks on the surface are not seen nor are objectional. The open joints help to control the moisture behind the wall itself.
In either case, proper drainage of the soil retained in necessary.
Dick
Engineer and international traveler interested in construction techniques, problems and proper design.
The concrete wall is more expensive in most locations due to the cost of formwork. Both are satisfactory solutions. Moisture penetration and staining of the exposed face tends to be more of an issue with block walls unless they are waterproofed on the earth side.
you can place drainage holes in the bottom of the wall at every 4 foot and paint the wall with a hydocide on the side where the back fill is you will eliminate most of any water problems. besides you can also paint the face side of the cmu wall to cover any kind of staining