Golf IV / Jetta IV :: 2009 Auto Transmission - Should It Be Flushed / Changed

So, I have a 2009 Golf City (Canadian mk4.5) with the 09G 6 speed Tiptronic automatic transmission. It's at 80k kilometers and shifting fine, I can remember maybe one 1-2 slip bump a few weeks ago but that's it. Shifts in Drive, Sport or Tiptronic are smooth and forced downshifts are smooth as well. I do want to follow the US service interval of 40k miles, and of course, my dealership won't do anything with this transmission unless it's broken because "Your fluid lasts the life of the car sir!" That, of course, we all know is BS because every transmission wears, and I don't want millions little metal shards of hardened steel having a party on the inside of my transmission.

This being said, I know that you can do a pan out filter and fluid change, but your only getting about 5L of fluid of the 9L that the 09G has. Or I can pay a local trans shop to do a full flush without dropping the pan by tapping into the in/out fluid ports and flushing everything out. My worry about a flush is that it will take these little anarchist metal shards and put them in a spot where they get stuck and have an all out project X-style party with my solenoids, gears, and torque converter. And the filter still won't have been changed!

Or I do the former where I get the ECS Tuning kit, drop the pan and clean out these little bastards and put in a new filter and not worry about the last 4L of fluid that still might have some of these buggers in it...