Conceptually they seem to be showing the same information. But in the context of a Madden Julien Oscillation (MJO) or equatorial waves especially over the equatorial oceanic layers which one is more useful to look at: 1) OLR Map or, 2) IR Satellite Imagery (black and white satellite pictures of clouds)?
First OLR map is usually graded in flux units (W/m2) thus it is quantitative data, not just a visual picture.
Clouds themselves are not a very reliable indicator of high convection and thunderstorm activity. They could form elsewhere and get blown into a dry region. Also with an OLR map students would not be distracted with the shapes of the clouds.
AIRS OLR products combine infrared and microwave data. Microwave data helps to distinguish between areas of strong convection and nonprecipitating clouds.
Here is a typical OLR product from GOES satellite (taken from Hai-Tien Lee presentation). Such images can be generated with 15 minute interval so the movement of the MJO pattern can be easily observed.