Me three.
I don't see the appeal of 5160 for a folder. I can see the appeal of 1095 and given a choice between 1095 and 5160 for a folder, would pick 1095 every day of the week. As for the choice between Buck's 420HC and well done 1095... all other things being equal, I'd pick 420HC actually.
The Reaper (fixed blade) might be the smallest knife in the line that makes sense to me to do in 5160. It's designed for some amount of chopping.
The upgrade I'd like to see on the Spitfire is a full flat grind. I find the Slimline (the Walmart version) to be a decent shop knife but find it to be horrible slicer due to the thick blade and abrupt shoulder on the hollow grind. It's one of the reasons mine doesn't get carried too much.