If you are need to do 100+mph. K16GA has speed limited at 100mph, only B, GTL, and GT that can goes above 100mph factory.
Well and if you gold is speed, I can assure you that K engine is what you need highly addicted. Its scream louder than my GSA LC, is faster than R18. However, I'm not sure...
I have both R18 classic and K16GA.
If I were to choose again I'd go with R18 Transcontinental.
The bike this size POWER and speed is not that essential, comfort, cruising with plenty of torque is more important. Plus is a boxer engine, boxer is bmw.
I live in Bangkok so heavy traffic city is a no for my R18 classic, wide handle bar and big engine make it hard to maneuver around and lane splitting, trust me my Big K16 Grand America is easier to goes around traffic more than this Big boxer.