Taking the PSAT in 9th and 10th helps to prep for the PSAT in 11th and the SAT. My youngest is in 9th, so she'll be doing the silly PSAT 8/9 this year. I understood the old PSAT & SAT that my older two took - I just don't get why you should take a baby version of the PSAT instead of the real thing, but that is a rant for another day.
I think that the PSAT in 9th and 10th helped my middle kid hit the needed NM score in 11th grade. She didn't do much prep besides the PSAT, so just being familiar with the test helped.
In the end, NMSF/NMF didn't help her, but she knows that she could have chosen a college that would have been full tuition (or more) given the NMF status. It isn't the NMSC scholarship of $2,500 that makes the big impact, it is the schools that will give you tuition or more. Alabama has been mentioned, and a recent addition are some of the Florida schools. Their full ride NMF offers used to be just for in-state, but now they are offered to out-of-state students too.
Middle kid received a full tuition scholarship (not NMF related) to another school, but we asked her to apply somewhere where she knew she would get a large merit offer and would be happy to attend. Getting the needed NM score can assure your kid that they'll have some options for good merit.
One thing to remember is that the PSAT cutoff score varies by state - so it may be easy or not-so-easy to hit depending upon your location.
