Shimano Ultegra 6800 vs R8000

[CreakyCrank]

Ultegra 6800 at $750 vs new R8000 at $1100 for complete groupset. Is it worth the extra $$ ? I'm upgrading from 105.

[Duck!]

Depends what you want from it. The R8000 shifters have a slightly slicker action than 1st-gen 11-sp, which would be the major reason for upgrading. If you want even greater gear range capacity, or just the extra stability and lower profile of the Shadow rear derailleur design, or reduced likelihood of front derailleur fouling on wide tyres, a simple derailleur upgrade is all that's needed.

[li2099]

Coming from 6800 to 8000 for the derailleurs, I can say there's about 1% improvement in shift quality.
I haven't got the R8000 shifters so can't say about that.