If I am understanding correctly, the '13 Madone and the '14 Domane have the same components and wheels, and one costs $900 more than the other. Are you comfortable riding the Madone? Does it fit you well?
If you want to be able to ride faster, and the fit of the Madone is comfortable for you, and you're not having problems with discomfort from rough roads when you ride your Lexa, then I think the 2013 Madone is the right choice.
How about this -- you're considering a 2013 bike. We're well into the 2014 model season, so the shop wants to sell that bike. Will they let you take it on a long test ride? That would give you a chance to get a good feel for it. Ideally you can include a few hills so you can get a sense for how it climbs.
My Madone 4.7 was on sale when I bought it because it was from the previous model year. The shop manager let me go for a 30-mile ride with it before I bought it. I was concerned about the gearing being insufficient for the steeper hills in the area, and he wanted to make sure I was happy with it before I bought it. That test ride completely sold me on the bike. I realized after a few miles that my shoulders were no longer hunched when I rode, because the reach was better than my old bike. I could feel that the carbon frame absorbed the bumps from uneven pavement better than my old aluminum bike. And I was able to confirm that I could make it up a couple of steep hills with similar effort to my old bike.
Now I'm a regular of that particular LBS, which is probably one reason why they were willing to let me take off with the bike for more than two hours. But still, the shop you're dealing with might let you take the 2013 bike out for 45-60 minutes. It's worth asking.
- Gray 2010 carbon WSD road bike, Rivet Independence saddle
- Red hardtail 26" aluminum mountain bike, Bontrager Evoke WSD saddle
- Royal blue 2018 aluminum gravel bike, Rivet Pearl saddle
Gone but not forgotten:
- Silver 2003 aluminum road bike
- Two awesome worn out Juliana saddles