This is one of the best baselayer style fleece we've ever tested. It's super warm for its weight, incredibly comfortable, highly versatile, and very attractive. This fleece outperforms all of the similar fleeces we've tested from other companies that are not included in our comparative review (e.g. Mammut Kala Patar Tech, Rab Baseline, Arc'teryx Konseal, Mountain Hardwear Desna) and one model that is (Patagonia Capilene 4 Hoody). The Eclipse Hoody's distinguishing attributes are: (1) long torso that tucks under pants, pack waist belts, and harnesses to prevent it from riding up and exposing your back and/or stomach; (2) long arms that keep your wrists covered even when your hands are overhead; (3) phenomenally comfortable and protective balaclava style hood; (4) lightweight and highly breathable material. The other similar models we've tested have one or more of these attributes, but not all of them. The Eclipse Hoody weighs 10.7 oz. and is our new favorite fleece for backpacking and one of the best for climbing.
The Eclipse Hoody competes closest with the Patagonia Capilene 4 Hoody, but we prefer the Eclipse, on average, because of its longer length and more protective hood increase warmth significantly- to the extent that the 2.5 oz. weight penalty is more than offset. The difference becomes more significant if you use an ultralight sleeping bag that doesn't have a built-in hood, are on the tall side, or venture out in winter temps.
The only significant drawback to the Eclipse is its moderate total warmth. For an extra $20 the Patagonia R1 Hoody offers more warmth and, consequently, is a slightly better all-purpose fleece.