i have the original climashield j58-ws and the j68-pl, they are pretty much the same thing regarding warmth. in action the insulation via elastic hem wins vs the speedlock.
while i find the j68 visually much more pleasing and interesting as standalone, i dont think it is a great midlayer:
- no shell connection
- the collar of your shell can feel pretty tight (2.2 haters spotlight on)
- if you get to a quadruple speedlock scenario with your shell, you are in for some annoying fiddling