The lightest I can think of is AM's Valkyrie which is unusable on the road whilst this car very likely will be (obivously not as much as something like a 720S), and doesn't possess a hybrid system anywhere near as complex as the W1. 1.16kg/hp for the technology the W1 possesses is no small feat. I forgot to mention the Valkyrie uses a single clutch transmission to shave even more weight, McLaren doesn't do that. I can't think of any non EV apart from the Tourbillon making these specs look standard, most manufacurers are having similar levels of power with 1600kg+ dry weights (a.k.a SF90, Revuelto, AMG ONE,and Tourbillon again.) so the W1 is in a pretty safe spot right now. The only potential threat is its direct competitor : The F250.