I'm in a somewhat similar situation - my DD14 took the SAT in 7th and 8th for CTY/SET/TIP. As she's already taken it twice, we're going to take this year off.
She'll take the PSAT next year to prep for the NMSQT version the following year (though I doubt it's any different), and then SAT in late 10th and 11th.
It sounds like you're considering the PSAT in 9th, not the PSAT 8/9. If you are going to test this year, I'd recommend the PSAT - the 8/9 seems to be of no value, IMHO.
For others who may be reading with a DYS student in 7th/8th - I highly recommend taking the actual SAT towards the end of 8th (and once before as practice, if possible). The student gets experience with the actual test, and it comes off their records as if it never happened. But if the student does manage a very good score (as mine did, and I suspect other DYS'ers could), you have the option to keep it and have a score "in the bag" well in advance of college applications.
