I read a post where someone used unflavored gelatin in their MMF and so I tried it. I've been using marshmallows, water, crisco, a tsp of vanilla extract, and a pack of knox gelatin in all my batches.. However, they don't always come out as perfectly as I'd like them to. Sometimes they're just too flimsy to work with or it begins to tear, etc.
So I'm seeing more and more posts of people that use Karo syrup. Would I need to use this instead of or in addition to jello? Would this help my situation? And how much Karo? And does it matter if its light or not?

Thanks in advance

oops, forgot to mention powdered sugar... obviously that's part of the mix too