A rival paradigm gaining some currency of late is the IGB image, which can be constructed by the above two-exposure method (and will be below) but in practice is more often obtained with a converted camera and a special filter or stack of filters and a single exposure. Conceptually, this involves replacing the red channel of an ordinary visible image with an infrared exposure. Advocates of this method point out that the image looks as it does straight out of the camera, without the need of extensive processing, and that it lends itself more easily to video use than the other..
These two image types have both similarities and differences. To illustrate, a test scene was chosen which contained:
-foliage;
-a car taillight;
-red and green LED signage; and
-red painted surfaces.
Here are the constituent RGB and infrared images used in this comparison:

And here is the 2-exposure IRG frame of the scene as constructed, with minor post-processing:

In addition to the reddish-pink foliage color, one can see other signature characteristics of an IRG image. The red painted surfaces and car taillight now show yellow, due to the reflection of both red and infrared. The red LEDs now appear green(ish) and the green LEDs appear blue. The sky is somewhat obscured by chronochromic fringing due to cloud movement, but the top shows the characteristic deeper blue color, less green than in an RGB image.
Here is the two-exposure IGB image of the same scene:

As initially constructed, due to the large amount of green light coming off the foliage, the vegetation appears orange rather than red, and the sky is more cyan than in the other images. Substantial hue adjustments were necessary to make the image more similar to the other. I do not own the relevant filters myself, but it is interesting to note that some users of filter stacks have also reported vegetation coming out more orange than expected. In passing we note that the red painted surfaces and taillight remain red and the green LEDs remain green. The red LEDs are blacked out.
It is not the aim of this post to claim that one image type is inherently superior to the other; artistic taste is a matter of opinion and there is no right or wrong here. Rather, it is hoped that the difference between the image types will have been clearly enough elucidated that informed choices are made possible.