Since you are looking to dip your toes into the test waters that is bicycle touring, I would recommend starting with your 1220. A lot of cyclist buy all the gear and either find out they don't like it/ it's not really for them or simply don't have the time for it. I would recommend panniers that have the angle cut to increase heel clearance, since your Trek has 42 cm (short) chain stays. Your Trek should have tapped holes in the drop outs (I used to own Trek dealerships, and know that bike) 5 x.8 mm threads (waterbottle cage size) they likely will have paint in them. you will need to use plastic coated p-clips for the seat stay mounts. Make sure that you get a dedicated pannier rack that has the supports that stop the pannier from rubbing/ going into on the spokes. For instance; Do not use a Blackburn MTN rack.