G'day Hodgo,
I'd go the 760 slammer for longtails as it has a bit more up its sleeve for retrieve than the 850ss and still has heaps of drag capacity too.
I have both, no problems with either and the chinese build quality is not an issue for me - its been performing fine - only real difference is the chinese version, you can't replace the main bearings which affects the rebuildability/maintenance side of things.
You're just up the road from me, I'd be happy for you to trial both the 760 slammer and the 850 spinfisher so you can feel the difference before you commit to buy.
Let me know if that is an option you would like to explore
cheers
Rhys