As someone with long history of insomnia, much worse with stress but often not an issue when stress is low, I would include myself among those whose sleep this product improves. I stopped Skullcap for over two weeks to be sure the effect wasn't from that, since initially I reported some success after starting both at the same time.
I get back to sleep much easier after getting up (darn near fall asleep on the toilet occasionally ). My Fitbit sleep record, for what's that worth, is very good. I'm getting good amounts of all stages of sleep with fewer than normal amounts of unconscious waking (not to be confused with apnea, which I don't think the Fitbit detects). The difference is notable. If I push my bedtime out too late it's not as effective, but if I get to bed around 9-10 my sleep is deeper and more stable.
Nobiletin may be worth our investigation for more reasons. According to a 2014 study:
When researching materials from natural resources having anti-dementia drug activity, we identified nobiletin, a polymethoxylated flavone from the peel of Citrus depressa. Nobiletin exhibited memory-improving effects in various animal models of dementia and exerted a wide range of beneficial effects against pathological features of AD including amyloid-β (Aβ) pathology, tau hyperphosphorylation, oxidative stress, cholinergic neurodegeneration and dysfunction of synaptic plasticity-related signaling, suggesting this natural compound could become a novel drug for the treatment and prevention of AD. [Anti-dementia Activity of Nobiletin, a Citrus Flavonoid: A Review of Animal Studies]
It has widespread effects, so dipping in at this early stage may be a bit risky:
Recent evidences show that NOB is a multifunctional pharmaceutical agent. The various pharmacological activities of NOB include neuroprotection, cardiovascular protection, antimetabolic disorder, anticancer, anti-inflammation, and antioxidation. These events may be underpinned by modulation of signaling cascades, including PKA/ERK/MEK/CREB, NF-κB, MAPK, Ca2+/CaMKII, PI3K/Akt1/2, HIF-1α, and TGFβ signaling pathways. The metabolites may exhibit stronger beneficial effects than NOB on diseases pathogenesis. The biological activities of NOB have been clarified on many systems. This review aims to discuss the pharmacological effects of NOB with specific mechanisms of actions. NOB may become a promising candidate for potential drug development. However, further investigations of NOB on specific intracellular targets and clinical trials are still needed, especially for in vivo medical applications. [The Multifunctional Effects of Nobiletin and Its Metabolites In Vivo and In Vitro]