I'm sure both companies will tell you that 'they are the best' and cite many reasons.
You might consider telling us what conditions you intend to wear the coat (other than cold conditions)....skiing? backpacking? Everest basecamp? Walking to the bus stop - in Miami?
Activity pays a huge role, i.e. easy walking to strenuous climbing in the snow with a heavy pack!
Do you intend to 'layer up'? so you can de-layer to keep body temps on an 'even keel'?
Also, how cold? 40's, 30's, 20's, negative 20?
There a dozens of other brands out there that would say their coats are pretty nice also.
It usually comes down to your intended conditions and what 'fits your eye.
And both will fit a bit differently, too. I have my preferred brands because I like the way they fit my body.
I am a long time Patagonia fan - bought my first fleece jacket forty years ago and still wear it. For all that Mountain Hardware seems to be a decent outfit.
The questions asked by Phil Reed are quite pertinent, especially anticipated temps...
You might find this evaluation useful https://www.outdoorgearlab.com/topics/clothing-mens/best-winter-jacket?specs=n&n=0&sort_field=#compa...
I have found their evaluation of other items on targeet in the past...
@Heathertinseth627 often our answer to this kind of question is: whichever fits you best! Both brands make great gear but their fits are different - arm length, fit through the waist - those will vary. Can we help you decide between a few styles?
Hi @Heathertinseth627 .
I can't dispute any of the advice provided so far, but would like to add some additional thoughts for your consideration. I personally own some Mountain Hardwear and some Patagonia, as well as some other brands such as Outdoor Research and Sierra Designs.
I can say that the fit, aside from your own personal preference and appearance, will affect how it performs under the conditions you intend to use it in. A snug fit in a down jacket may look more flattering, but could compress the down such that it minimizes its ability to insulate. A loose fit may allow for more layers, but allow drafts when those additional layers aren't used.
Next thing to consider are the features such as breathability, pocket size and placement, hood adjustability, ability to stretch and flex. This falls squarely into what @Philreedshikes mentioned about your intended activity. If you are climbing, flexibility is paramount, as is a hood designed for a helmet. Backpacking may dictate pockets positioned to accommodate a hipbelt on your pack. For bushwhacking or labor-intensive activities you may want something with a more durable face fabric.
I hope this helps. Good Luck!