I consider myself to be quite the "luggage cough". I've actually been told to seek help regarding my odd love of buying luggage! Anyway, here's what I've discovered.
- If you need a very big suitcase for whatever reason (slightly more important now that Qantas have their "1 Bag" rule), don't go cheap. They get very heavy and it needs to be a good quality one. I bought a mid-range bag from Myer and the roller handle snapped off mid-trip. My previous large bag was a lime green Qantas branded one and it lasted about three years of good solid travel. Eventually the fabric on the side gave out. I've decided now that for a large and often heavy bag, you should go hardshell as it's less likely to break. I now have a blue Samsonite hardshell that has click latches on the front and both sides (with turn locks). I'm pretty happy with it, however I'd probably go a zipper next time as it makes it a little easier to squeeze shut. Be careful, as this large size will always be about 30KG and that can upset a lot of airlines. I purchased the current one in New York for a bargain of $160. Expect $300+ here.
- I have a "mid-size" bag that I use for trips of about 7-10 days. It is a black Samsonite fabric with orange accents. From memory it came from Strandbags and was about $200. It's a good size to usually weigh in at 20kg. I have done 4-5 RTW trips with it and it has realistically been on ~300 flights and is going very strong still. I had one repair when the front pocket ripped however that was handled well by Samsonite and they have a good network of repair shops (took a week and cost me nothing).
- I've just swapped Cabin Bags. I previously had a Tosca 115CM bag that Qantas were always happy with, however Virgin have kicked up a stink and I had to replace it. It was nice and solid, but a little big and the bag itself weighed in at 4kg so it realistically wasn't the right option. I bought a nice Antler 105cm cabin bag online from Luggage Direct. it was ~$100 delivered. So far, so good. Weighs 2.4kg empty (so leaves about 5 for you) however it is a little smaller than what I'm used to. Does the job for overnights or weekends though (provided you can wear your jacket). The quality of the Antler bag seems very good (on par with Samsonite) and its got nice touches like leather handles instead of plastic.
My rules are don't go cheap and nasty but stick with quality, well known brands. Can't go past Antler or Samsonite (I'd never buy anything else). I have used a Jag bag in the past however it didn't last long. Myer or DJ's often have 40-50% off sales or Luggage Direct etc always have them heavily discounted with free postage. You'd be stupid to pay full price for any luggage items in the current discount climate.
I gather that you must be flying QF Business or, as you are Gold , you get the extra luggage allowance. A 30 KG bag will cause dramas now in Y class with Qantas or Cathay. I was using some Qantas points recently, and flew Y from BNE to Shanghai. My bag was 21.4 KG at check in in BNE and no problems.
In Bangkok, on the return, it had grown to 25.9kg ( dont ask me how),and I was hit 5,000 baht excess baggage.
I always use soft Samsonite Suitcases. I had one for 10 years, and it would have done at least 200 flights when I was working in Asia Pacific. It had four wheels, and while it was heavy, it was the best suitcase that I ever used. I have also used a few hard shell Samsonite, but, these were in the 90's, and were a conventional suitcase. I prefer soft cases now.
My latest case, is a 4 wheeled Samsonite vertical spinner.. Very good, except, if the balance isnt correct, it can topple over.
In fact, I also purchased a cheap 5 wheeler in Bangkok, that has an adjustable 5th wheel. Can be moved further out to stop the case tipping. Works well. All for Aust. $135 or so.
I always put a few bright coloured luggage straps on my case, as it helps on making it stand out at the baggage carrousel.