I used to if I wasn't carrying scuba gear or other large items but these days I'm too frequently flying in countries or on airlines that have strict weight limits on carry on. Back in the old NW days I used to get 2 weeks worth of stuff in my 21" roller, so it would fit anyone's sizer including HK Airport's, but it'd also be about 40lbs, well over the 7 or 8 kg most airlines I fly these days allow. I'll still do it when flying the likes of UA, NH, or OZ but tougher on many others.