My PG son has a 40 point gap between his PRI, VCI and processing speed. It's not really an issue. I think the way it manifests is, he takes longer than expected to do his homework (part of it is perfectionism issues), and he sometimes stumbles on words-- has trouble with retrieval-- when he's excited to talk about something. There's a bottleneck of words trying to get out. Other than that, we haven't seen any problems.
Is your son having problems of some sort? If not, I wouldn't really worry about it.
