If your DD is neutral, I would nudge her to try it. Expected and unexpected benefits may accrue. We registered through NUMATS because DS and DD were only 12 and couldn't register online otherwise. As a result, they participated in the College Board study where they got to take a second (new version) SAT for free plus received a giftcard for their participation. We subsequently registered with CTY as well for the ceremony (closer than NUMATS) and the one course scholarship donated by colleges. I was pretty sure that DS would be awarded a scholarship but was pleased that he got one from a prestigious college rather than a mediocre one. A summer college course is within our plans in a couple of years so it's nice to save a couple of thousand dollars in tuition. However, I was surprised that DD also received the same scholarship because her scores weren't even SET (700+) level. Your description of your DD fits mine as well - not a math genius and not likely to absolutely kill it on the reading section. DD's scores were only around DYS level but I think it helped that not just one but all three section scores were strong and she can obviously write based on the SAT essay. Her Reading score was the strongest of the three while her Language/Writing score was the weakest. If your DD is strongest in Language/Writing, consider registering with CTY instead because it looks like they will be using the combined reading/language (EBRW) score rather than just the reading subscore moving forward. CTY also gives a giftcard to students who qualify for the Grand Ceremony and provides a free lunch and campus tour afterwards. I don't know much about Duke TIP but NUMATS also awards top scorers although it's not advertised so I was surprised when DS received a $600 tuition scholarship useable on NUMATS courses.
In addition to the potential monetary incentives, there were a couple of other benefits that I had not considered at the time they tested. DS and DD can automatically enroll in our community college system without any placement testing. The requirement is scores no lower than 500 all three (Math, Critical Reading and Language/writing) sections. More importantly, DD in particular has been inspired to pay more attention to academics, work on her language skills, maximize her other standardized testing scores, and contemplate college and career options.
