I'm running 404 on my asian 880 with either 41 or 50" bars. Of course, I hopped it up a bit, so milling with 404 is no issue for it. The downside is that it has a lot of compression, drop starting with the bar over the log is the only way to go. The plus side is, nobody wants to borrow it to mill with. For ***** and giggles, I took it to work one day...bad idea, one of my coworkers almost dislocated his shoulder, trying the "OSHA approved" ground start, when it halfway fired and then recoiled back.
I've done a bit of falling with it, but those were big hardwoods. Even on the big trees, my hopped up 066 or " 566i" are just the easier saws to run.