>>36122102Anon pretty much hit it on the head.
Beckett is far stricter, and because of that, tend to cost more.
PSA is still strict, but not nearly as bad as Beckett when it comes to certain things.
If you don't care too much about resale, just send it to PSA. You can set the lowest rating you're willing to accept, and if it lines up, you have a graded card. If not, it's sent back to you as you sent it.
I have plenty of PSA 10s of my favorite mons and favorite character (Plumeria) for my personal collection. It's pretty safe to say if I sent a few to beckett, they would be 9.5s.
I wouldn't be content with a 9.5. I'm sure you'd be in the same boat if you want a certain rating.