Turn Arduino into an ISP programmer

so, how long should a USB AVRISPmkII take to burn a bootloader, e.g. ATmegaBOOT_168_ng.hex or ADABOOT_168.hex, with the Arduino 16 IDE Burn Bootloader? (the former is 5700 bytes, the latter is 4800.)

it's taking about 10 minutes on my G4 Mac 10.4. if this is not normal, what is the best way (on a Mac) to increase the ISP comm speed?