New here but my thoughts
T30 - I have used them on track (four times) at donnington and also on a cbr600, they were great and get hot really quickly. They do however lack a little 'feel'. they must be quite a hard compound. In the wet they were good, better than most tyres out there. I haven't used them on anything bigger than a 650 though but they made the bike much more flickable.
I have just put PR4 on my K1200 s (and spring ST 955i) and they are epic, I can ride just as well in the wet as i can with a set of cheaper tyres in the dry. Dry use is also ace, knee down all the way on the sprint. I have only had them on the K1200 for 200 miles so difficult to be sure but riding in these monsoons we have been having they are worth the cost without doubt.