So when i'm grinding i'm unsure if its best to just do one big long grind, or keep changing between the grinds (hitting the face buttons X/Y/B) does anyone know which is best for score?

Or is grinding just not really good for score?

I usually grind until it becomes "Huge", then try and jump and do an air trick which is also hopefully Huge, and then land and continue grinding until jumping at the end. Why? Because huge and massive tricks increase your combo (at the bottom, max 20x). Grinding doesn't seem to give all that many points anyways though, so trying to do air tricks off jumps is preferable, unless its a great rail leading up to a huge jump. It really varies by length of rail though.

To specifically answer your question, its better to hold the trick because you'll get more points once it becomes "Massive", and unless you're needing to build your combo up to 20x before the end of the run to cash in your trick combo, its better to keep holding it instead of switching it up.

Gridning while in "Yello Tricky" mode until huge add 10k to your combo bonus, combined with 20x multipler is 200k per grind. I find this is the best to do, ie grind until huge than switch to a seperate grind

^All above is true. However, I use grind to get into Tricky and Super Tricky. Which comes faster when mashing out different grinds. So it depends on what you want.

Awesome, thanks guys, you helped alot, I just used to hammer on the buttons, switching the grinds every second or so. I'll try what you guys are saying :)