DH and I did this separately. First he did while DS (4) and I did the buzz lightyear spin a few times. Then, I did Stitch while they ate lunch. This was our first disney trip since we went separately 20+ years ago so nothing to compare it to. DH loved stitch...told me it was a must do. I thought it was ok, but was expecting a bit more action because of the harnesses.
Both of us agreed that this would have scared our 4 year old senseless. I talked to a couple of moms later about the ride. 1 had a 9 year old boy who screamed the whole time and she was powerless to run to comfort him. Another had a younger son (maybe 6) who liked it.
Stitch was cute as normal, but the attraction is intense especially for little ones really learning about their senses. If you have children going on this, I strongly recommend gauging their personalities before having them do this.