Haven't tried the graphene spray and probably won't for some time. I still have a lot of Beadmaker, Polyseal, and Optimum car wax on hand. For fun the other day I mixed 70/30 Polyseal and Optimum Instant Detailer. Why? Well, OID flashes well and has great gloss, but has no durability. Polyseal is also a great product but is just a little finicky on the application - wet towel, buff after application, etc. I've only tried it once but the combo of Polyseal and OID worked really well! Slicker finish, even easier to apply, and I think it has more gloss. Who knows. I have no idea how long this will last on the paint and simply *hope* there is no long-term reaction between the chemicals.
That all said, Graphene-based products sound interesting. But, I think I am at the point (actually have been) at the point of diminishing returns. The gains are all incremental...not transformational. And I just end up spending more $ and having more product sitting on my shelves