I spent several hours in DA last night after work, and this was my 2nd visit (went to TM preview the first night). I rode HE express both ways before my friends got off work, but the first thing I did was go into DA, get a Tongue-Tying Lemon Squash, and parked my butt on a bench outside The Hopping Pot, to relax with my drink. It was DELICIOUS! Super tart, the way I like my lemonade, and fresh squeezed too, not from a nasty mix.
After my train rides, picked up my friends, and we spent almost 3 hours in DA, not even riding HE, and had the most wonderful time. One of us had an interactive wand, so we played with that a lot, and we managed to go into most of the stores (almost 3 hours, and STILL didn't make it into all the stores), and just marveled at the incredible detail everywhere. The line for the money exchange was too long for us to deal with. Had a great dinner at Leaky Cauldron (and adults can order the kids meal, which I loved, because the kids' fish and chips was the perfect portion for me), and later in the evening we all got ice cream. Just such a wonderful night with good friends, and I still have more to see, like, I really need to catch both shows in their entirety.
I can see DA itself being an all-day experience. Words cannot describe how wonderful, detailed, and completely immersive this area is.