Just like the mini's, who makes the biggest with these features?
Takeuchi makes one in the 15 ton range I think.
Depending on what you need the blade for there's this, 17.5 ton machine: http://www.kobelco-usa.com/north-american-excavators/sr-series/ed160-3-blade-runner
I have always thought that would be one heck of a mountain road builder.
Takeuchi TB1140 is the biggest I've seen with a swing boom. There are probably others, but that's the biggest one that I know of.
I've got TB180FRs with the "slewing boom" (9 ton). And a PC128UU-2 with a 3pc offsetting boom. Since they don't make the PC128UU anymore, I've got my sights set on a 314ELCR with a 3 PC boom. Like this one. http://www.constructionsalesau.com/2004-caterpillar-cat-314-clcr-excavator-for-sale/7818/ They still catalog it as a "power offset boom".