We've used this bag for our last two, month-long, UK trips. We only do carry-on when we travel.
http://www.walmart.com/ip/iFly-Carbon-Racing-Hard-Side-Luggage-20/28997853
iFly Carbon Racing Hard Side Luggage, 20"
Flew British Air both times (2013 & 2014). Each of us ( 14 year old son, husband & myself) carried our own bag onto the Seattle-London flights with no worries. Held more than enough clothing and rolled like a dream through airports, the actual plane aisles, the Tube and through streets. The hard shell made it easy to slide into the overhead bins on the planes.
The four wheels act independently and very smoothly, so you can either pull it behind or push it ahead of you on two wheels, or you can roll it upright, on all four wheels, next to you. Very well-balanced, they never fell over, even when we used the expansion feature.
The extending handle has two height settings. So, little 5'2" me could comfortably use the same suitcase as our son (5'9", at the time) and my husband (6'6")! The regular is very easy to hold, as well.
Honestly, it's the best suitcase I've ever had. We bought 3 more and have stored them in our guest cottage, in case the three we've been using ever break! The only suitcase I will use, particularly for overseas travel.
Not pricey, either! Got ours at W-Mart.
One last thing: a hotel manager friend told us that bed bugs have great difficulty climbing hard, smooth surfaces (like the suitcase I describe here). An entomologist friend said the same thing. A little bit of peace of mind when leaving suitcases unattended in lodgings (we also put our luggage in the bathtub when we are away from the room)!
