R1200R Tire Experience
I have Metzeler Z-6's on the bike and have found that they work superbly. The secret may be the pressures: The Service Manager at my dealership (a very knowledgeable guy, ridiculously fast, with tons of track experience) recommended 36psi front, 42 psi rear rather than the 32/36 psi shown in the owner's manual. He said he ran these pressures even in the wet and on the track. I realize that this sounds counter-intuitive - - usually one uses lower pressures for quicker warm-up and extra grip (e.g., on the track) - - but it works like crazy. My riding is mostly canyon-carving and the Z6s feel super-stable all the time, even at full lean. Moreover, with 5K miles of hard cornering on them so far, they are showing very little wear. They also have a slightly more triangular profile than the Pilot Roads and turn in a bit more quickly. I have also put in about 5K miles on Z6's on an R12R in the Alps (twisty, lots of very tight hairpins, often wet, sometimes cobblestones) and had the same delightful experience.
If you don't care for the Z6s (even after trying them with the higher pressures mentioned above), you might want to try the newer Z6 Interacts. They have received uniform rave reviews from the mags and on various rider chat sites. The newest tire in the line is the Z8 Interact, but I haven't seen any reviews or performance comments on it yet.
BTW, I used Michelin Pilot Roads (both #1 and #2) for tens of thousands of miles on my previous K1200RS and would unquestionably rate the Z6's on the R12R as better-performing, recognizing that we're talking about two very different bikes. The Michelins felt quite good when new, but a lot less so when more than half worn down. Moreover, they never quite inspired total confidence in full-lean situations. However, they did get the best mileage of any tire I tried on that bike (a real tire-eater, due to its hp and weight), so I stuck with them.
I have heard good things about the Bridgestones on an R12R, but they were a disaster on the K1200RS.
Everyone's taste is different, and you've gotta go with what makes you feel comfortable. Take this for what it's worth; hope it helps.