Big park. That being said, it is not very good. The "street" section is very spread out, you need to push a lot. All the ledges are about the same height, low. The banks are a bit steep with very little transition at the bottom.
There is a "pool" in the back but it just doesn't seem to be built correctly. Getting to the coping is almost impossible.
Then there is the bowl section. For some reason the bottom is not level. All the locals start at the same spot, ride down to the oververt wall and then come back. There are not very many lines in it. The spine is impossible to air. Most of the coping is impossible to get at.
The bathrooms are clean and there are pay showers by the tennis courts. Entrance fees are 500 yen The staff is mostly older adults that have never seen skateboarding before. They are totally unreasonable and enforce the rules like the SS. The park is very far from any train station. There is a bus from Hachioji station that runs once an hour, it takes 40 minutes from station to park.
Bikes MUST have plastic pegs and pedals.
Bottom line, not worth the time it takes to get to this park. Although it is big there are better parks that are easier to get to in the Tokyo area.