Was perusing REI recently and saw the Brooks LSD II wind jacket, which i previously had never heard of. The listed weight for a medium is 4.3 oz, and i did a breathe test on it and then on the Houdini which i have heard a lot about. To my surprise and subjective perception--the breathablity seemed rather similar. But that wasn't only it, even the back of the head, hood cinch system was pretty much the same.
One big difference besides price, was the Houdini is made out of nylon and the Brooks LSD II is made out of polyester. I think there are both pros and cons to both. On one hand, polyester is innately more warm (pro or con depending) and noticeably more innately hydrophobic than nylon (so it will dry faster, especially when the DWR's wear off), but on the other hand nylon is stronger and a bit more durable. When dealing with such thin materials to begin with, the latter is definitely an edge. Re: the warmth of the poly Brooks jacket compared to the P. Houdini, the former does have more innate venting which probably makes up for that.
The Brooks LSD II was on sale or clearance for 58 dollars. The Patagonia was 99 dollars. I'm aware you can get the latter cheaper at some online vendors, down to around 60 not including shipping in some cases. However, i wanted to be able to easily return it if i needed to or didn't like it.
So i figured 58 dollars was pretty much within my current budget if i worked a little extra on the weekend, which i have the option of (but don't like to do)... (Shhh, don't tell my wife, but i did get the Brooks jacket, it's hiding in my trunk--this, my double life as a gear junkie/whore/secret agent... oh, what the heck, i spent 50 dollars easily yesterday on stupid and completely unnecessary stuff for the vaunted "valentines" day)
Ok, so it's no Montbell Tachyon or the like (i would like to get the Stoic Wraith if they actually had it in stock), but i think the Brooks is a decent choice for the poor man's light(ish) windshirt.
Edited for correction of an error.