I just got the Ortlieb Back Roller Classics yesterday and biked to college today with them packed to the brim probably 30+ lbs. So far they are great. Bumpy roads didn't budge them from the rack at all and they were relatively easy to carry them with the strap to class. I have a feeling I will find many uses for them and maybe make some to trips to the grocery. At the beginning of the year I ordered the Patagonia Black Hole Messenger Bag which offers ample room for a big laptop but it was too big for me so I went with the Patagonia Half-Mass Messenger Bag. Only down side is it's not very big and isn't waterproof so that's why I bought the Back Roller Classics.