A problem I have with panniers is that after I arrive at my worksite, I have to walk several hundred yards with two bags. Unfortunately the bags do not have a good system for walking, although they are fine on the bike. A solution I have created in the past is a DIY backpack to which I added pannier hooks. Unfortunately, I am waiting for someone to give me a good candidate bag, hopefully one without too many zippers (zippers are the weak point in most bags...); I suppose I could go out and buy a bag...