Gear review: Paradox DriRelease thermals from Costco

Three years ago, I wrote an article title Outfitted by Costco.


The ruggedly handsome model is posing against the suitably majestic mountains. From the Paradox website.

I’ve been happily using Costco gear for many of my outdoor pursuits.  Since I’ve written that article,  I have made excellent use of their uber-luxurious and high R-value pads for winter car camping.  Additionally, I have been using their new and improved flick lock poles, keep various headlamps stashed in the house for emergency use or night-time bike riding. And the Kirkland-branded merino wool, Smartwool type, socks are almost a daily mainstay.

And something else I’ve been using for over five years as of 2018? The Paradox DriRelease merino blend brand thermal tops and bottoms.

I decided to do this review for two reasons:

  • These thermals are discounted at some Costco stores right now. A top and bottom set can be bought for ~$30 or so while still available.  (And, both the men’s and women’s versions are discounted on eBay, too)
  • I’ve had these thermals the same amount of time as the 100% merino wool base layers I just reviewed. Yet the Paradox layers are less expensive, been used more days total, and show trivial signs of wear vs. the merino wool base layers.

First, I should say right off the bat, that calling these base layers “merino blend” is a bit of a misnomer.

They actually are a polyester blend with a bit of merino wool. The breakdown is  84% poly, 11% merino, 5% spandex.  The shirts consist of something called DriRelease embedded in the poly fibers that allegedly help with odor and wicking. I am not an uber-technical gear guy, so you may want to read up on the specifics yourself.

So, how do these gussied up polyblend thermals work in the real world as opposed to laboratory settings or on a spreadsheet?

First, they wick well enough. No better or and no worse than any other poly layer I’ve used. Odor? I’m sorry, but if you are sweating, all the clothing is going to stink at some point esp on multiday trips. Even the wool layers it seems.  That’s what I found anyway.

And though too much spandex in thermals in a significant amount can be counter-productive for cold weather clothing, I found the small amount of spandex in these layers to be a non-issue for real-world use.

The layers themselves are a touch heavier fabric than a light base layer, but not quite as thick as a true mid-layer.  Perfect for hiking in the typically cool and dry Rockies when the weather turns. Even in summer, I’ve worn the thermal top by itself on many early mornings starts. Probably overkill for say the Southeast Appalachians in prime season. A lighter layer shirt is likely to be excellent for a chilly evening. But for the backpacking and outdoor activities I do, it is a versatile layer for three seasons and beyond uses.

A men’s medium top is about 6oz, and the bottoms (men’s large) are 7 oz. I like the zip-top, and take an ounce or so weight penalty, as I find a zip top is a more versatile piece over many conditions over a crew neck top. Part of my gradual evolution that means looking less at specific ounces and more for functionality in a lightweight framework.

(As an aside, Costco has even lighter base layers on sale currently. Both regarding weight and fabric. They are also crew tops.  I have not used them myself, however). 

At the end of 600+ miles on Canada’s Great Divide Trail. And over five years after my initial purchase.

These simple Paradox thermal layers work rather well.

Over the years, I found with gear that will get used up and replaced (socks, thermal layers, and so on) that the adage of “You get what you pay for” is not always true.  More and more outdoor clothing is essentially highly-priced luxury goods as opposed to something four or five times better to go with the four or five times more expensive price tag. Better …maybe? Concerning its price, probably not in my humble opinion.

A Jaguar is much more expensive than a Toyota Corolla  (or insert affordable, but a reliable car of choice. I like my Kia). But the Jaguar is more likely to be in the garage getting worked on by a mechanic. Or pick a Lexus, perhaps more appropriate. You get the idea. 

Don’t have a Costco membership? Amazon sells these thermals in both women’s and men’s sizes for competitive prices, too!

Overall:   The Paradox thermal layers are a simple, affordable, and reliable economy car when it comes to thermal layers. I like them. And they work.

Disclosure: Obviously, I bought these Paradox base layers with my funds. Thrift stores, Costco, discount stores and surplus stores generally do not give away gear to bloggers whose biggest claim to fame is that he writes a good amount when not in his small beige box at work…

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8 years ago

Expensive cars are expensive to repair. While we don’t normally repair our base layers, I hate to spend a lot on something and get a tear in it or wear a hole in it. The things that I’m going to use need to be justifiably tough or reasonably inexpensive. There once was a time when I only wore Levis for work pants, but they were way too expensive. I had no real choice but to find something cheaper that felt comfortable. Most of my base layers now come from the military makers.

3 years ago

I got some great thermals from ALDI (a UK supermarket), cost me less than £10 I think, Get other bargains on brand names from TK Maxx. I only ever buy in the sale.

1 year ago

These materials stretch in weird ways. Pullin them over ur feet they snap up ur legs, requiring u to pull em back down. They don’t stretch enough to get over ur heel and cling to ur ankle. I find they require u to manipulate them at every curve of ur body to get em on. And getting em off… They don’t have enough elastic properties, Leaving u snug in some areas while loose in others. Maybe that’s why we don’t wear plastic bottles as clothes. Keep tinkering ur almost there.

1 year ago
Reply to  Paul Mags

Do you have any knowledge of the R value of this material in comparison with other synthetics?

Baba Jaga
Baba Jaga
1 year ago

I realized it’s not the merino but plastic bottles stretched to look like a fabric in chemical process. I do not think it’s healthy to absorb plastic via skin, same as consuming water from plastic bottle. So much talk about saving environment and allowing production of plastics and recycling in more chemicals. Recycling cotton, wool, silk sounds smart and real care of the earth. The biggest organ deserves to get a better fabric to touch. 11 % of polyester would maybe be ok (?)but not the other way. The advertising on box is misleading. Costco could do better as exemple.

Bill Ebt
Bill Ebt
3 months ago

I’ve been wearing them for 2 years now and I don’t like them. The ankle fit is all wrong and there is no ankle band. The whole thing slides up under outerwear.