More warmth needed – Add to torso or groin/legs ??

you dont need the insulation when active as you say … so the R1 wouldnt be as efficient

balancing out the insulation top and bottom would be better for sleeping as well

add a light weight hat. weighs next to nothing and will be way more versatile than extra pants or jacket. think about it.. everything is inside your sleeping bag except your head and you lose tons of heat through your head.

Indeed this is all about keeping yourself warm at night IMO, unless you're the type that likes to take long breaks during the day. Even then, torso warmth layers are a lot easier to put on and take off than anything on the legs.

Assuming that perhaps you just didn't list headwear that you already plan to bring, i.e., sticking to the torso vs. groin/legs question, I'd definitely favor the torso. For one thing, you can do most or every in-camp chore with your lower body in the sleeping bag. And you already have long johns listed.

On the AT early last year the temps got down into the teens several nights. I used a WM 20F rated bag with down booties (highly recommended for cold temps, feet in particular can be an issue), a down parka, but just thin long johns and my normal hiking pants on my legs. This combo worked great for me.

Hi Guys

Just to clarify I will have a Blackrock Down Beanie and Wool Balaclava.
Feet will be fine as I have some fluffy light poly socks and spare merino walkers in case. + some bread bags as a VB if it's really bad on my feet at night.
My sleep system is a 3 season wide burrow by hammock gear with 2oz overfill.
Exped UL Syn Mat under me.
I'm not worried about the sleeping part being cold.

Even when stopping I don't think any extra layers will be needed/wanted as the daytime temps are quite hot. Maybe a nice icecream will be most desired but that's unlikely….

It's just camp when that sun drops and early mornings. Apparently the thermometer plummets once that sun drops over the horizon in the desert. I'm thinking the down pants as they are very light and will give me more overall body coverage.
Not keen on walking around wearing my TQ, that thing drapped over me and sharp spinifex grass is asking for trouble.
There are three of us so I'd imagine a little camp time at night talking s#$t like usual. No camp fires though other than the bushbuddy !!

I'm not one to really get cold legs either but I do understand there are some major arteries running through the upper legs and groind. Maybe keeping these warmer would do the same thing as adding a vest or more upper layers ?? I guess that's my question as I have no idea ??

Again, this is a style thing, but for the situation you're talking about I'd just leave the down or synthetic pants at home and get the lower half of my body into the sleeping bag as soon as possible. You can do almost everything "half in the bag". Heck, bring along a little everclear and you can do so in both meanings of the phrase, but I'm talking about spending all of your camp time with your lower body in the sleeping bag.

Group dynamics, however, are indeed what can defeat this. It's then a matter of talking to your hiking buddies ahead of time to get a sense for their camp-time expectations.

adding insulation to the legs does help when stationary …

again if its a choice between the R1 and the down pants … for what you described, id take the down pants …

the R1 is not very warm, and its really for active use