For the last 2 years I have used a Rivet Stratos jacket in both summer, and with a liner in winter. It is a multi-layered synthetic jacket with reinforcing in the back, shoulders and elbows. While it is waterproof, and warm in winter, I find it too hot in summer, even with all the vents etc opened. I plan to look for another jacket exclusively for summer use, which would not need to be waterproof, just cooler, but still with adequate protection. It would be used for both occasional commuting, and for day rides in and around Sydney. Before I put myself in the hands of the sales drones at the local motorcycle emporiums, I would like to take any suggestions/information about the suitability of different materials, constructions or brands of jackets. Any thoughts? Thanks David