I want to try to explain my previous post a little more. I hope this will make it a little clearer.
the way I use the Buddho meditation is by concentrating on the sound. This makes sound the object, using the ear sense and repeating "buddho", "buddho". This is similar to using a kasina, say the earth kasina as an object, using the eye sense and repeating "earth", "earth". When using Buddho in this way, it is not a long repetition of a text as for example shown in the visuddhimagga. It is just sound as an object of meditation using the ear.
Ajahn Chah used Buddho in a far more difficult way. He used Buddho as a mind object, using the mind from the beginning, repeating "buddho", "buddho" in his mind. Still it is not a repetition of a long text. Just Buddho as object of meditation using the mind. He used breath as an anchor, the way I use a mala as an anchor. His way is more difficult since the object is far more subtle then for example sound, to begin with. But in the end it is both the same object of meditation using (in the beginning) a different sense.
Now to the goal of Buddho meditation (and I hope all buddhist meditation). When looking at abhidhamma it becomes clear that each of the 5 jhana are just citta with a different set of cetasika. There are these jhana citta as fine-material spheres of absorption. But these same citta are also there in the 20 fold way of the supramundane path and fruition citta. The goal of buddhist meditation is getting to the supramundane citta, as they permanently eradicate defilements. Buddho as an object of samadhi meditation can lead to jhana citta because it calmes the mind, but far more importantly, it can lead to the supramundane citta.
Why do I say this? for some reason people have the idea that it is necessary to switch to breathing after Buddho. Or do something else before or after Buddho. Why? Experiencing Jhana as a fine-material sphere of absorption as a goal in itself has no value. It is only a timely suppression of defilements. Of course calming the mind is imporntant, and jhana citta are a result of this, but this is not the goal in itself. So why change meditation or do all kinds of different difficult things just to try and get fine-material jhana? If it is possible to use Buddho to get to supramundane path and fruition citta, is this not enough? Ajahn Chah is one example of a meditator using Buddho consistently and experiencing both jhana and path and fruition citta.
So, when you are interested in Buddho as object, find a good teacher who truly knows Buddho meditation. It can lead from beginning to end, no need to switch or change or anything. Just using "buddho", "buddho" is enough. Fine-material jhana is not the purpose of buddhist meditation, just a nice by product, supramundane path and fruition is the goal.
I hope this makes it a little bit more clear...