There is potential to move into full time. MAM is an individual company that supplies Qantas with Casual Cabin Crew members. However, it is not true that you don't have access to the staff benefits. There are benefits, but it's just a bit different.
On the topic of training, the 7 weeks are rather intensive so I would advise you all to get ready for it. If you have kids, unfortunately you will have to make a decision and see whether the job is what you really want. You won't have access to Staff Travel right away and the training times aren't set and are subject to change without notice. So I would advise you to have someone look after the kids while your away.