How do I determine the optimal length for a torso-length underquilt?

I'm contemplating ordering a torso-length Habanero underquilt from George for conditions that are favorable to save weight and bulk compared to the full-length Habanero that I have on order. George makes decisions for a hair-splitter like me a bit more difficult by offering one-inch increments for a fully-customized quilt. I see a variety of standardized lengths from other makers (e.g., 46", 52", 55"...). I'm seeking feedback from others on what has worked for them. Many thanks in advance for your suggestions.

The safer bet is to go longer, but I'm trying to keep my gear ultralight for backpacking. Lighter gear makes it easier for me to make it up the hills. :)

I'm 5'-10" tall. This will be a 40-degree (or perhaps 30-degree) torso-length quilt.

I'm 6'1"...I have 20F and 40F HG Phoenix 3/4 uqs. They are about 52" long. They cover me from shoulders to decently past my knees. The 40F gets way more use than the 20F. For below freezing weather, I found that I prefer the full length Incubator over the 3/4. If I carry a sit pad, the Phoenix will work but not wanting sit on the ground at camp...I bring Helinox Chair Zero instead.

I believe when hammock gear offered the phincubator it was 65”. UGQ does a 3/4 length at 66”. Those would be a good compromise. I’m 5’8” and the shortest I want is a 58-60”

I'm 5'8" and in warmer weather (>40°F) I've used quilts as short as 45" (Te-Wa... remember those?) and have been comfortable. But I'm good with anything from 55" to 65", and on the diagonal with the quilt biased toward the head/foot corners 65" is darn near full length for me anyway. :rolleyes:

Not asked, but I'll note that LL has the option of Argon 49 which I'd recommend for lowest weight and volume. Depending on specs for length and fill, a 40°F UQ might weigh around 10oz or perhaps lighter.

Many thanks for the inputs. It helps to know what is working for others.