The Corsa Speed are good race tires for good surfaces, they've been tested as having the best rolling resistance on the market by multiple sources but they lack a puncture belt so I wouldn't recommend them for the training or even racing on really bad surfaces. I only use them on my TT bike where the fact that they only come in 23c isn't an issue.

The regular Corsa G+ tires don't roll quite as well but they come in 25c and have good road feel and seem to be a high-quality all-around tire.

Right now my racing tires for the road bike are Continental Grand Prix TT's, which are almost as fast as the Corsa Speed but have a bit more puncture protection.