I'm flying V Australia Brisbane to LAX and then have to transfer to Airtran for a flight to Portland Me. Their checked bag allowance is 50lbs or 61 linear inches.
Because I'm going on a US motorbike tour, I'm packing my gear in a roll bag 31.5 ins by 16 ins diameter. Will Airtran be sticklers and argue that the L + H + W fig is 63.5 ins and therefore exceeds the allowance. My argument would be that cubed out, it is less than a rectangular bag that might be 61 ins.
V Australia won't make an issue of it but I don't know what the baggage climate is like in the States.

EDIT
I actually posted this at 5.30 am US time but in the wrong forum area and Flyover 23
has posted on the same subject area so we may be cooking this one twice.
Reading his/her thread, what I suspected could happen, has happened i.e the rule may be enforced quite literally and there's a disadvantage in using a roll shaped bag.
There will be some very tight additional straps to make sure that we don't have an upset in international relations