Can someone clarify for me the differences in these 2 bikes. The both seem to be road bikes with one being more aero than the other and a bit more stiff. But it seem they are meant for the same type of riding just for different types of riders?

thanks

You've got it- the Soloist is the aero/part time TT bike, the R3 is the more traditional frame- an uber-light 'climbing bike,' with a claimed best stiffness to weight ratio of any bicycle out there.

But it seem they are meant for the same type of riding just for different types of riders?

Not exactly...they are not made for the same type of riding. You usually wont see a CSC GC contender riding a Soloist to victory up the French mountains and you wont see a CSC rider going out on a solo breakaway for the stage win (flat route) using a R3. Not to say it can't be done, but a CSC rider usually chooses a frame depending on the days geographic route (along with road conditions). Going up a long mountain for a victory, ideally you need the lightest frame available with the best strength to weight (STW) ratio. The R3 has this covered. On long, smooth flat roads an aero frame would be ideal to limit your drag even if it's a small percentage. However the SLC-SL brings the weight down just above the R3 and still holds the aero advantage. It is a frame that a CSC rider could use in any stage of the TDF. Frank Schleck actually won the Alp d' Huez stage on the SLC-SL but the R3 is still lighter and has a better STW ratio. The R3 being Cervelo's lightest frame and being the stiffest in the bottom bracket and torsion means more power is being transfered and less lost during the pedal rotation...a must during Paris-Roubaix! Oh...and no matter if Cervelo says it made the R3 for one purpose and the Soloist for another, the rider can choose whatever makes them feel confident inside...