standard values of TRV (Transient Recovery Voltage)

For 132KV (rated voltage 145KV), 2000Amp 40KA Circuit Breaker, in case of Terminal Short Circuit faults, which standard values of TRV (Transient Recovery Voltage) i.e. "First Reference Voltage and peak value for representation by four parameters" are easy for the manufacturer to achieve considering 100% terminal short circuit with 1.5 FPC Factor

a) First reference voltage 178KV and peak value 249KV
b) First reference voltage 133KV and peak value 249KV

Please explain whether option (a) or option (b) above is easier to achieve for a manufacturer of the above referred circuit breaker and which option is better from quality point of view.