How much does an avanti cadent 1.0 weigh?

It is probably lighter, but the weight difference between the frames will be quite small. Alloy frames are light, the best ones rival carbon fiber frames. The difference between the 2 frames is probably much less than 1 pound. Normally, a bike frame makes up less than 20% of the total weight of the bike, so the quality and weight of the other components is at least as important as the frame material. More important than weight is the way the bike rides, how it handles, how it fits. Focusing on weight alone, you may miss out on what is relaly important to building a good bike.