I've flown both (Tiger - GC to Melb and JetStar - Bris to Melb) and never had an issue with either.

Tiger do seem to have stricter book in / cut off times, but as long as you get there with plenty of time I doubt you'll have an issue.

Service is fine with both... basic and you pay for what you need.

I think it's definitely a 'luck of the draw' kind of situation... I've had bad experiences with JetStar, Virgin and Qantas...

I would pick the cheapest... you're only on the plane for 2 hours... what could possibly go wrong