There isn't much out there on the street that will out accelerate a speadster. Speadsters don't have anything special when it comes to weight/hp. I've had plenty of ICE cars with better weight/hp ratios than a roadster. Why roadster pretty much rule the streets is simple:
100% of torque from 1rpm
Never has to shift (no time loss)
Put those together and it would take something with a weight/hp ratio of something like 1lb per 20hp to keep up. Roadsters are only something like 1lb to 11hp I think?