I have always used the OEM kit. Great piece of kit, but you need to remove the swinging arm to fit them.
Original lasted 40000 and did the second one, put on the 3rd OEM one at 84000 miles.
Having a scottoiler helps the longevity as does changing the front sprocket every 12 to 15000 miles. It wear 3 time faster then the rear.
Fitted a DID to the Fazer 1000 the and JT sprockets as I did not have time to wait for the OEM kit. 15000 miles on it at present and I changed the front sprocket after 12000miles. It also has a scottoiler.