While I'm not in the same class as you tour folks. I do have a small pannier trunk bag I use. It works great to carry tools and gear for day trips. This is the setup I plan on using for RAGBRAI and TOMRV this year. The last couple years I wished a had a bag to put things I bought in the thru towns. I think this Topeak RX trunk bag with panniers will work nicely. I also have the smaller trunk bag without panniers for in town commutes.