BD Firstlight hoody vs Arcteryx Atom LT

I have an Atom LT which I wear as a layer in winter and as a warm-weather puffy. Found a really good deal on a BD Firstlight hoody but not sure if it's worthwhile seeing as they are similar?

Anyone have both to compare?

I have an atom and a nano air (which I believe is similar tech).

Atom only vents really well through the side panels. The front and back are still somewhat plastic-baggy, but also more weather resistant. First light is breathable all round, but once the DWR gets dirty weather resistance is gone. Not an issue if under a shell. 

Sorta two different products. The Atom et al are intended more as stationary insulation pieces. The fabrics and insulation mean very low air movement and thus, breathability. The side panels on the LT were an attempt to help with that a bit before active insulation came along. The First Light is very much an active insulation piece. It’s basically an Alpine Start Wind shell with the active insulation under it. 

If the goal is a mid layer in cold conditions, the BD piece will likely serve you better as it breathes significantly better than an Atom. If your goal is a static belay piece with the wind whipping, it’s not going to keep you as warm as you’d like. 

You might also want to try TNF Summit L3 Ventrix Hoody. I have the Atom LT and the Nano Air, and have tried the BD First Light Hoody, and I like TNF Summit L3 Ventrix the best, because:

- Better fit than Nano Air, but just as stretchy, flexible, breathable and better over the helmet adjustable hood

- First Light Hoody, although durable, is not as stretchy and flexible as TNF Summit L3 Ventrix or Nano Air

- TNF Summit L3 is warmer than Atom LT, Nano Air and BD First Light, but with the breath ability of First Light and Nano Air, and just as durable as the First Light

- The over the Helmet Hood is not adjustable on the First Light (or Nano Air for that matter, since it's meant to go under Helmet), while TNF Summit L3 Ventrix (and Atom LT) over the helmet hoods are adjustable.

- Hand pockets on the First Light is positioned too low and is blocked by a harness, while TNF Summit L3 Ventrix has the best positioned pockets for harness, followed by Atom LT/Nano Air (tie). 

- The TNF Summit L3 Ventrix pockets are also conveniently large, unlike the small pockets of the First Light, Nano Air and Atom LT.

- First Light length is a bit too long (though some people like that) while TNF Summit L3 Ventrix and Nano Air are a bit shorter with Atom LT being the shortest length, all the same size. 

- The cut of the First Light and Nano Air seems to be tailored for really slim tall people, while TNF Summit L3 Ventrix and Atom LT have a more generous cut.

One thing I do like about the Nano Air, is the easily accessible dual chest pockets. TNF Summit L3 Ventrix, Atom LT and First Light have 1 inner chest pocket which is very inconvenient to get to. But of these 3 inner chest pocket jackets, TNF is the best.

^^^could not agree more. The ventrix (summit version) is one of my favorite pieces of kit of all time. And it's TNF. Go figure.

I’d guess at least $150 difference without looking

Another vote for the Ventrix. Quite possibly my favorite jacket I own. 

Damn, people are still investing in technical North Face pieces?  I might have take a look at em....  been a long time!