I bought Water resistant Tioga bags that have built in rain covers in the top flap. I wanted those bags as they had an extra bottle holder and separated compartments as well. It was $100 for all 4, from an LBS, and have been quite happy with them without the covers and light rain, and with the covers, in heavy rain. The rain covers are also yellow, so help in wet weather for being seen. You can also get decent waterproofing spray containers, better then S...... guard and lasts longer if you look around..