Carry on baggage, using hotel facilities (e.g. laundry) or doing yourself for undepants is perfect even for long term staying. Apart from this consideration (lots of "armored" packs here at www.pacsafe.com but expensive, or have a look at the excellend Osprey Farpoint 40) I believe that smart luggage is totally unuseful.
I have been travelling in the last four years using just a Benzi Ultimo 40 L carry on bag whose price is just about 19,99 euros and in a couple of months I'm upgrading to the Osprey Farpoint (for me) and the Osprey Fairview for my wife. They both sport laptop protected area and perfect straps including the waist one.