Time for tires again

Time to fit the 3rd set of tires on my bike , bought it with the oem Contis , did about 6k kms wth them then fitted a set of Metzeler tourance tires , What made me decide to fit them was the awesome review of durability the tires had at BIKE TIRE WAREHOUSE , the had a used set there as proof with 23000 k on it , my set has done about 15000ks , front is so so ok , and can do a couple more , rear is on its last legs but in a pinch could maybe do 2000 at a push , witch would return 17000 odd kilos , I must add that 98% of my riding has been long rides two up with full luggage ( top box & panniers ) so I am not complaining . Think they have been great , center has worn flat , but I have noticed that most rear tires on big adventure bikes tend to go square/ flat .
My 1st choice is another set of tourances , but also looking at options , the new Michelin Anakee is a contender , I have just never been a fan , also looking at the Bridgestone AX range , but a very new tire and litte info on them . As mention most of my riding is two up , and it seems the tires last me about 8 months , then time to fit a new set .
If you have the new Bridgestones on what is your take on them so far ? My feeling is that I have had great service from the Metzelers , and bar a intervention , going to fit them again in the next week or so .
We have booked another trip  over the August long weekend , again in the region of 2000 ks , and I am one of those riders that like to have good rubber on my bike , not prepared to tempt fate . this gives me a month to fit a new set .