So far so good with our 2014 x213! I just finished building shelves into the long and deep cabinet next to the bunks- that should help make the space more usable. There is a little storage in the dinette benches too, but not a whole lot.
I ordered a 2" memory foam mattress topper from Costco for about ~$100 including tax, as I found the mattress to be really uncomfortable.
So far have towed about 600 miles experiencing traffic, windy narrow mountain roads, small sites, step hills, etc. while I will not win a race with my set up it has felt stable and safe to me. And BTW I am not racing anyone! 55-60 average speed for me.
Biggest surprise so far: the $20 bridge toll for towing it across!