Andrew – thanks for the flash review.
I’ve had a Western Mountaineering Flash Vest for several years, and recently concluded it’s a specialized garment that won’t go on most backpacking trips any more. It’s also about 2 ounces lighter, uses 850 fp down, and probably less warm than the Eos. That makes it not warm enough most of the time.
The Flash’s YKK coil main zipper frequently separates at the bottom because it’s much harder to properly mate the starting points than any other zipper I own. Often takes two or three tries to get it on right. Since you also found reports of Cerium LT zipper problems, I hope you can report back on the Eos zipper after more experience.
One feature I appreciate on the Flash is stuffing into it’s own hand pocket without over-compression. Does that work on the Eos?
— Rex