I started with a synapse as my first bike, then wanted something that felt faster. I also felt like I was too "compacted" on the synapse if that makes sense. I thought I would alternate between my caad12 and synapse like I've done with running shoes. I haven't found myself wanting to ride the synapse at all in a year though. It feels super upright and 10x heavier now. I'm looking to sell it actually because it is just collecting dust now.
HTH