They handle very differently and have a very different driving experience. I will list some of the characteristics and say which kart I preferred for that feature and then will give a summary of the two karts. (And I'll make sure I am not bias)
Stability: ERA
Acceleration: Bugatti
Steering: Bugatti
Braking: ERA
Fun: Equally fun
Driving comfort: ERA
Most spacious: Bugatti
ERA: Beautiful CycleKart, Very comfortable and because the seat is narrow you feel more connected with the kart. The pedals are very soft to press and are larger. No large brake issues. Turning requires more force but doesn't require much rotation. Great fun to drive and thank you Chris for letting me have a go!
Bugatti: Beautiful CycleKart, Comfortable seat but because it is wider you slide around when driving creating a more raw driving experience. The pedals require more pressure to press which I like. Brakes work great when cool but heat up quickly. Steering is easy and doesn't require much force. More rotation is needed to get round the corners but this is by no means uncomfortable. It is overall my favourite CycleKart that I have driven so far.
I hope this has helped
