They seem the same to me (hell they look the same).
There are two things I hate about aluminum cases:
They all leak. No matter what, don't even try to tell me yours doesn't. I've seen vehicles with 20,000 miles on them that leak with aluminum cases.
Slip yokes just suck for many reasons and they're the only thing I hate more than the leaks.
Other than that, they're lightweight, strong enough to take a thrashing from the right foot, etc.
208 and 241 use the same parts kit for the chain so I'm not thinking either is stronger.