Here's a topic for us all:
The 3D Sonic games (Adventure, Heroes, etc.) have always had a bad rep. What is YOUR personal opinion of them?
With me, here's my opinion of all the 3D sonic games I've played:
3D Blast: Hated it. It's not real Sonic at all. Very difficult, and way too many "Kill all the enemies to move on" points.
Adventure series: First one was horrible, the second one was... meh. It didn't have the feel of Sonic. Also, a lot of the graphics were rather ugly.
Heroes: This one, while it did have the same 3D style of Adventure, it regained some points with its unique team-style of gameplay, switching formations to get through certain areas, it was fun. By no means did it meet the standards of the side-scrollers, but it wasn't horrible. About a 7.5/10.
That's all the 3D ones I've played.