We place ours just under halfway, 1.4m from the foot (3m hammock body) I agree with the stress mentioned above but if you reinforce 10+ inches along that hem you will be fine, ours is stronger as the loop is sewn into the zipper as well as the hem which adds to its strength, also it helps if you don't sit to far back into the hammock when you get in and out. UL gear needs a little more TLC!!!
Thanks for the feedback!
I'm doing the hammock out of .75 cuben with no sewing, all bonding. The hammock body after finishing the hems should be ~2.6m long, and I was planning to put the pull out at about 1.2m from the end. Based on your feedback I am going to double my planned re-enforcement area for the pull. I don't plan on having an integrated bug net though, so I am worried about the stress around that area. I've thought about glue attaching a section of nanoseeum bug net between the pull out and the body though so it helps hold stuff in.
Totally agree on taking care of your ultralight gear.