Hi Andy
The 81 is a stronger blank, I don't think the style of join has that much to do with it. In terms of an allrounder, the 81 is probably the most versitile. I used it a lot at Christmas Island with FCL Ebipop EXT120's poppers and FCL CSP200 and 220 stickbaits. I probably caught 20+ GTs on this rod over a few days and found it to be a very comfortable fish fighting tool.
The 80 is an excellent lightweight rod for working poppers and sinking stickbaits but the stiffness will make surface stickbaiting more challenging.
There is new rod in the works, the 81MH, which is rated to 17kg max lift. I hope to have some more info soon to post on this rod.
Cheers
Duncan