I asked about H&V /Play & Dine before our trip (first week of Dec). The majority of posters adamantly did NOT recommend H&V.
We held onto the lunch ADR, kind of waiting to see if we ended up at DHS at the right time. We hadn't had any big lunch meals, and were at DHS all morning. So we got right in at our 11:20 lunch.
It was one of the better meals and character interactions! It certainly beat out Chef Mickey this trip (I was severely disappointed at CM; the entire thing was rushed and the breakfast food was in poor shape).
Maybe because we were first seated for the lunch buffet at HV, the food happened to be top notch, warm, fresh? The selection was wild! So many options (and I don't eat meat, yet there was still plenty). Everything tasted delicious too (we were all raving, and my mom doesn't like ANYTHING

)
My husband is 'meh' with buffets but even he was impressed.
High scores for cleanliness, too.
Now, my 2 toddlers aren't so into JoJo, but of course they *swooned* at meeting her and Goliath (who is adorable). The characters spent a remarkable amount of time with the kids (the place wasn't packed, so that might have helped), lots of goofing around and laughs, and hugs.
Of the Little Einsteins, Leo and June (June is my dd3's favorite of that group) were there, and my daughter happened to 'match' June's purple attire and head band, so they were adorable together (my dd also has dark hair and eyes so they made quite a pair). Again, lots of interaction, multiple 'visits'.
I was pleasantly surprised, as the reviews were not at all good. I might have just been lucky and hit it at the right time, but we'd go again based on our experience. Again it was lunch, no Fantasmic show.