I ride about 3 - 3.5 miles to work, which isn't much, but I live in San Francisco, so there are hills, and I deal with fairly heavy traffic many days, so that short ride can feel longer. I also have to carry up to 20 pounds (occasionally more) to work and back, which is over 15% of my body weight.

Currently, I have a nice big messenger backpack, which I really love, but it does make me feel like I have less maneuverability, and my ability to stand up for hills or starts is diminished. It can also be really tiring.

I'm wondering if panniers might be a better fit for me. Typically, I have to carry my laptop, several files, and often some books (I work as a legal researcher, so think gigantic law books). I have looked at some panniers that look all right, but I don't want to spend the money if they won't be much of an improvement, so I am curious what you all think. Will 20 pounds in panniers be easier to deal with than 20 pounds on my back?

Thank you!