I've been planning to buy an R1 Flash pullover from Patagonia (clearance priced at $58 on Patagonia website), but STP has Lowe Alpine Micro Grid pullovers for just over $22 after the combined discounts. For anyone who has been considering an R1 pullover and wonders how Micro Grid compares, here's an explanation that I received from Melanzana:
Our Micro Grid fabric is actually lighter than the R1. It is 100% polyester where the R1 has some spandex mixed in. Therefore, it does have more stretch than the micro grid but it is heavier. We like the micro grid fabric because it is light weight, keeps you warm, and is very breathable."