We started with a 24/32, and three weeks after we bought the tandem we got surprised by a rough hill on an event. We just figured it out, spinning away at 80rpm doing 3.4mph. It was tough to handle but we survived, and we've been glad we had it. This season we had to put on a new cassette, so now we're running a 24/36 for Seattle hills, and I'm liking it.