I forgot that you went for the 200's. I actually love the sound of the nanotubes too. Especially the CKN70's. Mine are going on 60 plus hours now and I notice the changes already. The treble was bugging me at the beginning but its tamed some. It's a full spectrum sound on that little earphone. Sounds huge to me and among the top iem's so far no doubt. As for tips, I like the stock tips for some reason. I usually go with Auveo's with many of my iem's but FXZ's are tricky with fit so the stock works well for me. Can't wait for you to get your amp and especially those 70's.
Maybe because of fit issues, I found the 200's to be hit or miss. Sometimes they were excellent, other times not, adjusted some more, changed tips, would be okay, then not okay. Had a heck of a time getting the right tips and fit.
The ckn70's on the other hand, fit well, and gave an excellent sound after it's burn in period.