If you get 105 makes sure it's the 11 speed version, as that's basically the same as the current Ultegra. There are still a lot of 10 speed 105 bikes in shops, and that's a very different beast.
I'd be quite wary of buying a Canyon (or anything else online) as your first road bike. You really need to try some out and work out what size you need - bike fits can only go so far.
@GrahamP
If you get 105 makes sure it's the 11 speed version, as that's basically the same as the current Ultegra. There are still a lot of 10 speed 105 bikes in shops, and that's a very different beast.
I'd be quite wary of buying a Canyon (or anything else online) as your first road bike. You really need to try some out and work out what size you need - bike fits can only go so far.