What should make you think that VT is something to tests for? There seems to be a lot of optometrists around here who try to enroll all the kids they test into a full course of treatment (at around $5,000) so I have been leery of trying it.
OTOH DS7 is still reading weirdly (gets lost and reverses direction in the middle of long words, reads words out of order, mistakes b for d and p for q, skips words and lines entirely) and I have a gut feel that something is wrong, even though he currently reads 2 years above grade level.
My husband says he is the same as he was, his brain just runs too fast, and my husband is the only person I know who reads faster than I do (and I have been tested at ~900wpm with >85% comprehension rate).