I agree that a GT pro is always a good idea, but I should mention that our SB tester is one of the nationally acknowledged experts in the area of GT testing. Seriously, like one of the biggies! We actually travelled to see this particular tester because of the expertise factor, and that's one reason DS6 didn't sleep well before the test.
Seriously, MUCH experience...and books published on the subject of GT ed! This was not some newbie, so I don't think that was our particular problem.
My guess? I think my son's sleepiness had a lot to do with the long test time. The SB tester didn't even do extra tests with DS6. Just the required ones.
Still, the SB tester told us that it takes 90 minutes-3 hours for the SB if the child is GT, and it took our son over 3 hours!
OTOH, the WISC was just barely over an hour, and that tester even threw in an extra verbal subtest at the end to soothe her own curiosity. This second tester was a different, local one, who is experienced with GT, but young and not a nationally recognized old hand like the first tester.
Weird.