The underquilt works great, fits my Skynest hammock perfectly, and keeps me warn down to about 0 C. It is a little bulkier than I expected and is hard to get back into it's stuff sack, which is already coming apart at the seams where the draw cord is (the stuff sack, not the quilt).
There is a lack of instructions on how to attach the underquilt and I accidently pulled one of the non-elastic cinch cords out of the underquilt. Consequently now there is no way to tighten the underquilt up against the hammock on one end and it just hangs loosely down. There doesn't seem to be a way to repair it as each cord end is sewn inside the underquilt. Support asked for pictures of the damage to evaluate repair options, but their email account won't accept attached pictures or even links to pictures, and I am not sure they are even receiving my email any more.
My advice is do not pull too hard on the cinch cord as it may rip out of the underquilt with no way of re-attaching it. Other than that I have no complaints.