As stated, a 1000cc Blackbird is a completely different beast from a 125cc trainer.
A 1000cc sport bike like a Blackbird or Hayabusa or similar has the same or better performance as a F1 car. Very high power and low weight gives acceleration and handling that requires a lot of experience to ride safely.
There is a saying...
There are bold riders and there are old riders, but there are no old, bold riders.
I was a bold rider. I very nearly killed myself on a 250cc bike.
To address your question, an M3 is quite expensive. You can get a new sportbike for GBP10k or so. A second-hand one is much less.
An M3 has a lot of safety features, such as airbags; safety cage, crumple zones; ECS and so on.
A bike has few of these. There is only the helmet, leathers and pads to protect the rider from his/her mistakes – and more importantly, the mistakes and unpredictability of other drivers.
My advice: spend more than you can afford on boots, leathers and helmet. Spend more on your own safety and protection than on the bike. My helmet and leathers saved my life. Literally.
I would never get on a high-end sportbike, because it is almost certain I'd kill myself.
You need to find out more about your style of riding before you get on a sportbike.