Okay, sorry for the long delay but we finally moved in. The best speed I've been able to obtain is 17,000 to 19,000 down (vs. 30,000 promised), while the uploads are consistently as promised in the high 4000s. Here's a link to my most recent decent test;
However, I'd say that 90% of the time the test just freezes in the middle of a download, so most of them come back with super-slow indicated download speeds (with consistently good upload speeds). I don't know if that accurately reflects my "real world" performance or if it's a quirk of the test, as I haven't noticed such "freezes" in my time so far on line (streaming a lot of financial data in concurrently running programs, although not really streaming much video yet).
This week TWC is supposed to come back and swap out the router for the same brand as the one I have now, but with the telephone modem built in-- according to the installation tech, it's called the "wideband with phone" model.