I have heard of the 3.8 engine supposedly going 200k miles but I only know of one personally at just over 100k miles and it is a 2008. There are a few members on the forums that well into the low to mid 100k range.
Personally, I feel it is not different than any other engine/transmission combo, it boils down to how it was driven and maintained. I keep very detailed records on all of my vehicles but I know that is a thing of the past anymore.
If you could find one that the owner had all the maintenance records and could show its history, that personally would set my mind at ease a little.