Sad to hear that about Brooks. I always expected them to last a lifetime. I also prefer the B17, had 1 Professional that I liked equally, but sold the bike.

As to breaking in, I have 3 Champion Standard that all were good within 300-500 miles. Also have 2 Champion Special that took much longer. Got them years ago when it was rumored Brooks was going away. 1 was Green, I put it on my touring bike & logged more than 2000 miles before it just began to break in. The other is Honey, & put it on a bike that is seldom ridden. Roughly 500 miles & still looks & rides almost like new. My grand kid will have to finish it. I'm light, so even "as new", they are fairly comfortable though. Don