Late to party, but I can add some detailed personal experience.
I have been riding a C59 (DA9070 Di2, 303s) for a couple of years (20,000km) and am told by all that the C60 has the same beautiful handling and comfort etc but is just a little bit stiffer.
I tested the F8 (DA9070 mechanical, Mavic Kysrium SLSs) for two weeks in the Italian alps (1,000km, 30,000m of altitude gain
) so got a really good feel for it.
C59/C60Pros: - Perfect handling, utterly predictable tracking, handles hairpins and sweepers with complete confidence whether smooth or bumpy.
- Comfortable all day, including 200km+ rides on chipseal and gravel roads (yes, I know, taking it on gravel is rough on the paintjob but it's a testament to the handling that I can pretend to be Cancellara without fear of coming off!)
- Very responsive, no lag, and feels damn fast to me. I used to race more or less full time so I like to think I know how fast feels
- It's white, the Italia paint scheme, and looks so beautiful it hurts. Good thing I like cleaning it tho
- There aren't too many of them around which gives it some exclusivity.
- I willing to bet a lot, well actually the cost of the C60 I have my eye on, that the C60 will be the same but better.
Cons: - Not many cons, the biggest would be that when I sprint hard out of the saddle it can feel like the back wheel is unweighted and skipping a little. Maybe rider error, getting too far over the bars, but doesn't happen on my Colnago CX-1.
- The seat post was slipping at recommended torque (5nm), but a bit of carbon friction paste fixed that. Still annoying though.
- It's got a fiddly unique headset design. Takes a 2 or 2.5mm allen which requires great care not to strip the bolt head.
F8Pros- I really liked this bike. I spent a couple of days on a Dogma 65.1 first and it didn't feel good. Onto the F8 and I felt at home, as though I had the C59 under me. The F8 was a WAY better bike than the 65.1
- This is a really snappy and responsive bike, but in a predicable way. The handling is definitely a little sharper than the C59.
- Very comfortable - 6+hr days in the saddle and no complaints. It's not quite as comfortable as the C59, but pretty damn close.
- Corners like a dream, I could stick it hard down descents of the Stelvio, Mortirolo and Gavia with complete confidence.
- It's pretty light, albeit not even close to WW heaven
- It feels super fast, same as the C59.
- I think it looks really nice, and those forks really grew on me. Obviously a very different aesthetic from the Colnago.
Cons- The wheelbase is shorter than the Colnago (both size 57) and the toes on my size 47 shoes hit the front wheel on super sharp uphill hairpins, forcing me to take a wide line. Annoying, and the guy I was talking to said I probably could eliminate this by going one frame size larger.
- There are a lot of these around, including a worrying number of counterfeit ones, so they have less exclusivity than the Colnago.
Overall both bikes are killer. I am seriously contemplating buying a F8 next year when I go back to Italy, but then I look at the C60s in my LBS and get all excited as well. I'm actually going to wait to see how the disc-brake testing in the ProTour next month pans out as, if it takes off, we're all going to be buying disc-brake bikes in 2016 so we don't look out of date