Having been a student for 3 versions of this qualification and now lecture in it I would say there are a couple of things to consider.
1- how much time do you have to commit to the course? Some training providers do intensive 1 week sessions and then give a large project to complete at the end within 6 months. Others have the course structured longer with face to face time every couple of weeks and a more balanced workload.
2 - how much would you use it in the workplace? If it was for the qualification only I would do a shorter more intensive course. If you are interested in the process and being able to put the skills and knowledge into practice I would take a bit more time and the more structured course approach.
3 - online vs face to face, I would say the same as above, since its a course where the fundamental skill is being able to train and assess having face to face time is much better than just theoretical learning of online.
4- cost! In all honesty courses that are over $1500- $2000 are way overpriced. Most government institutions like tafes and unis run this course on a regular basis and at a reasonable cost.

I hope this helps a bit. Let me know if you need some more advice, I work in training, learning and development so should be able to assist