Replacing the axle is an involved process. Not 'hard' per se... but there is a lot to take apart and put back together when changing an entire front axle. It has actually been described in detail in Isuzu Tech a few times. Depending on their hourly rate, that is probably about right.

As for the breakage being common... I'd love to see their reasoning behind that statement. I have seen Isuzu front axels take a ridiculous amount of pounding with bigger tires and lower crawl ratios than stock, and have only ever been there for one breaking. I know plenty of people have broken them from reading the posts around here... but consider the situations they are being put in at the time <img src="/forums/images/graemlins/shiner.gif" alt="" />