I won't say they're perfect for everyone, but... when it's right, it's right.
I'm in process on my R-12 series (a 200k per month, for 12 consecutive months), and over the summer I rode 4x 200k, 2x centuries, a 300k and a 400k, all on a B-17 Imperial saddle. Next year, I'm signed up for more than 8 200k distances, 4x 300k, 2x 400k, and a 600k. They will all be done on my B-17 Imperial.
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"I feel like my world was classier before I found cyclocross."
- Mandi M.