The V-10 has been known to go well over 500k miles with proper maint. The 5 speed is also very solid and dependable as well as the rest of the chassis.
Have it inspected before purchase.
With that low of miles make sure to run the generator so you can see if it can handle the loads put on it from the ACs and other AC appliances. It shouldn’t surge when running under load or at idle. If it hasn’t been serviced it will need it. Low hours on a generator are not a good thing, they need to be used or they have running issues. My 2012 has 450 hours on it. You will want to see at least in the upper 200’s for hours.