RH,
there have been a number of incidents in canada involving 500's with blades cracking. some have caused the aircraft to crash with at least one fatality.
i have personally had cracked blades found on the machine that i had been flying almost exclusively for several month previously and i can assure you that it had not been over-torqued. not at least by me. this was doing seismic in the prairies which involves many torque events in a short period of time. the fatality that i refer to above happened to an outfit that did/does shake-block flying on the coast and it did admittedly happen to a machine with PMA blades. this is why MD came out with that silly inspection to be performed after 200 torque events or 25 hrs. 200 torque events isn't many when doing production work.
the 350 series can indeed keep up with a 500 in pretty much every way when it comes to production work. in an astar an experienced driver can fly a longline just as effectively as a 500 driver it just takes more experience/practice/skill. call it what you will. where the 350 shines is that it can carry enough fuel to actually get some work done before having to go for more, it is as robust as any other design that i can think of if not more, engineers love it because it is easy to work on and will designed, it is comfortable for both the pax and pilot, the heat and demist work at all temperatures without having to have tubes run all over the cockpit. i could go on but i just did a day of longlining in my astar at 7500 feet carrying loads that are probably at least twice what a 500 would carry under these conditions and doing it just as quickly but much more efficeintly.
admittedly the 600 i do not know much about, except one of my former colleagues is now dead because one fell apart on him. for years before his accident he had referred to the 600 that was in our fleet at the time as "Christine", like the car that steven king wrote about.
the 900/902 are apparently decent aircraft and i'd like to try one out one day, but you wont catch me in any of the other hughes/boeing/MD pieces of garbage.
bye for now
FP