Just watch this

(and the Fith gear test top left at the end)
There are differences, just depends on your car. If in doubt, try it yourself

It will take a few tanks to completely flush the old stuff out and the ECU is there to compensate for the changes.
People usually overlook Torque levels and go straight to BHP.
But in answer to your question:
I use Regular Shell in the CRV, Used BP-Ultimate in the Honda Integra and I use V-Power Nitro+ in the Abarth 595. So just depends what you want from the car. More mpg, power or cheaper fuel costs, it's up to you.