Great,your chains show no obvious signs of wear yet,after all of 700 miles,and you are prepared for a catastrophic eventuality.I am pretty sure they are not likely to break any time soon,you can allways adjust them and the sprocket design is such that they are not likely to malfunction.I was merely pointing out, that unnecessarily using such small sprockets in the primary drive is just not good engineering practice,Both the flexing angle between links on the sprocket and the chain tension are inversely proportional to the sprocket diameter,so chain and concomitant sprocket wear go up rapidly as it's size is reduced.Putting a new chain on worn sprockets causes rapid chain wear,you have to replace both.If the chain had been running in oil it would be a totally different matter of course.They just about last forever.
As far as the frustrating lack of info on the Dax site is concerned,possibly they are short staffed,even so, don't they realize that this is how they present themselves to their potential clientele ?, it's a no brainer really. As far as I am concerned they should present pertinent information on their own accord.I am not the first person who has expressed frustration with this lack of info.I am glad you like the Titan kit and have confidence in it,I had to settle on the Staton/NuVinci setup because of the steep hills around here,it works fine,but is heavy and pretty expensive,a 2 speed Titan had it existed would be just the ticket,lighter,probably a lot cheaper,easier to install and live with and with your 21 speed drive still intact.