My kids took the PSAT a few years ago, when it was on a 240 point scale. My daughter scored 230 her sophomore year, but dropped to a 226 her junior year. We were surprised, but she still qualified for NMF.
My son only got a 201 his sophomore year, but after taking honors adv. algebra and honors English, he got a 220 his junior year. He missed the semifinalist cutoff for our state by 3 points, but I think that if he had done more rigorous prep, he would have made it.
This test is worth preparing for because it can earn you serious scholarship money.