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Hands-on Gear Review
Cons: Expensive, limited durability
The 'Icebreaker Oasis' might sound like an oxymoron, but we found some truth to its naming. This long underwear is warm enough for a crow's nest iceberg watch in the North Atlantic, yet breathable enough to wear while riding a camel in search of a Saharan date palm watering hole (on a cold desert night maybe). Unfortunately, due to the limited structure of our award system it did not take home any prizes, although, it came awfully close to displacing the Smartwool NTS Mid 250 Crew for the Editors' Choice honor. This top exhibits great performance in many categories: warmth, breathability, drying speed, and comfort. We also like the styling for any social engagement, and its technical attributes qualify it for any winter adventure.
Along with the other merino wool options, the material raises durability questions. For a burlier base layer we recommend the Patagonia Capilene 3 Crew, but this top should be considered by those looking for the highest in performance, without concern for strength.
RELATED: Our complete review of long underwear - men's
OutdoorGearLab Editors' Hands-on Review
This is the base layer with the densest woven merino wool we saw. It was the overall favorite of at least one of our testers, but lost out in the final standings due to just a couple details.
The 200 g/mē merino wool on the Icebreaker Oasis provides a moderate level of insulation compared with the others tested, and results in a top weighing 8.2 ounces in total. We think this medium warmth is ideal for giving a shirt the maximum number of uses. It is warm enough to keep you toasty in a blizzard as the first layer in a multi-layer system, yet light enough on its own to let heat escape during vigorous exercise at moderate temps.
Smartwool NTS Mid 250 Crew, but not as well as the Patagonia Merino 2 Lightweight Henley.
In the air dry test, this shirt finished in a cluster of three tops just behind the fastest drying, Merino 2 Henley. The actual time was 20% slower, but that leaves it far ahead of the worst finishers. When you combine this strong showing with merino wool's resistance to absorb water, or even feel wet, you have an even better performance.
From the breathability and drying speed metrics we know that this shirt works great as a next-to-skin layer, but its relaxed fit allows it to also substitute as an insulating layer over a thin shirt. This capability gives you options for truly cold weather and even more uses for an expensive purchase.
Merino wool clothing needs to be handled carefully, and the Oasis is no exception. This top is susceptible abrasion, and caution should be used when machine drying to avoid shrinkage. The fabric, however, will not absorb odors like a synthetic so it should not have to be washed as frequently; extending longevity.
The denser weave of the Icebreaker fabric relative to the Smartwool led one tester to speculate that it would be more durable. We saw the logic in this theory but were unable to substantiate it in our tests.
Comfort and Fit
The uses for this base layer are nearly unlimited. From low to high intensity, frigid to mild temperatures, it performs well. The attractive styling increases its potential from backcountry adventures to a fashionable night on the town. The 50+ UPF rating for the fabric makes this a good option for particularly high sunlight scenarios.
At $90, the Oasis is 5 bucks less than the closely comparable Smartwool. Neither shirt is cheap, but with their quality construction and attentive designs, you receive a lot of value. When handled with care, both tops should last for many years.
Across all of the performance metrics this base layer never came in first, but its strong finish in each category resulted in a well-balanced and functional top. There could only be one Editors' Choice, and after much frustration, we went with the Smartwool, but some of our testers still disagree. Thorough shoppers should take a close look at this shirt because personal preferences in weight, warmth, or styling could easily make this your particular favorite.
Other Versions and Accessories
Oasis Long Sleeve Half Zip
Oasis Short Sleeve Crew
Oasis Long Sleeve Half Zip Hood
— Jack Cramer
OutdoorGearLab Member Reviews
Most recent review: March 30, 2015
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