Afraid I have to disagree with MuffDiver on BT-023's lasting longer than A40 or A41's. I've just put 4,500miles on a set of BT-023's found them very confidence inspiring, but there is now a noticeable step on the rear where the compound changes. I reckon another 500 to 1,000miles will see the rear off. Two set of both the A40's and A41's went between 5,740 and 7,126 miles but didn't see the same wear pattern. Loved the BT-023's but have just bought a pair of A40's as the price was too good to miss. A40's are a bit harsher ride than the A41's due to very stiff sidewalls.