Best Simms and Patagonia Fly Fishing Vests, G3, Guide Vest, Headwaters, Freestone, Vertical Guide. Our fishing vests are exceptionally well-made. We offer four models of Simms fly fishing vests with different features and carry capacities to address almost any fishing style or enviroment. Whether you like to bring every fly box you own out on the water, or prefer a more minimalist approach, there's a Simms or Patagonia fly fishing vest to meet your needs