Survey data used to be around 2x the current value when they were introduced and trust me, they were way too valuable. Finding a few Cat Vs in the begging of the game would mean skipping the early frigate game stage entirely and jumping straight into cruisers and capitals. The way I see them now is that they complement other things you find in the fringe. AI cores, colony items, blueprints, commodities, experience, etc. As you do them you start to get a good feel of where you want to plop down your colony.
That said I wish there were more uses for them.