Originally Posted by WhyFi

I recently switched from a 2018 Domane SL5 to a Cervelo R3 Disc. I don't know how the R3 and S3 compare in terms of compliance, but the R3 does a pretty good job in that regard. The R3 doesn't soak up road cracks and seams like the Domane does, but it's a more lively, responsive ride and I'm at the point where I find that an acceptable trade-off, even for longer rides (caveat - I've only done a few 60+ mile rides on the R3 in the month and a half that I've had it on the road - based on those, I think that it'll be just fine for 100+, but I haven't done that yet).

If you're looking for a more enjoyable ride, and the S3 has similar DNA to the R3, I'd give an enthusiastic endorsement.

....but if you're expecting consistently and significantly faster times from just the bike change, I'd say that you might want to temper your expectations. Unless you're moving to a bike with a more aggressive geometry, and you're able to take advantage of that more aggressive fit, you're not likely to see a huge difference. Also, I'd say that as the rides get longer (6, 7, 8+ hours), the more it's in the Domane's wheelhouse - the cumulative effect of all of those bumps can add up, and that can significantly hamper the human body part of the performance equation. In an ideal world, you'd keep a bike like the Domane around for really long rides and have a more fun, lively bike around for the shorter stuff.