Hi Sharz87
Look i can't speak for working for Jetstar because I have never worked for them myself, but I work for Virgin Blue and I can tell you it's a great place to work, and the money is great. There are alot of REX crew who have moved to Virgin and Virgin love them because of the skills they have developed to manage a cabin solo, work independent, and deal with a range of issues that arise due to working in a solo environment.
With regards to overnights you can expect to get 10 - 15 a month with Virgin, and lately all the rosters have been trips we rarely do day trips, its always overnighting. So i guess you need to figure out if you want to be way alot, or work for Jet star where you always get to be at home.
Another thing Virgin is expanding sooooo much in the next 12 months that there are so many opportunities, within 6 months you can get Cabin Supervisor especially someone like yourself who has prior experience.. Furthermore, with International starting that is always an option as well.
Good Luck.. Go VIRGIN, im biased though..