It could climb to 36000ft (11km) in less than 3 minutes. It could pull up off the runway straight into a vertical climb although this wasn't optimal. Apparently it could intercept at 65000ft and this was tested against the U2. It could go supersonic without afterburners in level flight.
All of this gave it relatively short range but it suited its purpose.
It apparently had very good handling but it was full of complicated systems and very powerful so therefore would be a scary thing to have an unexpected flight in.