Now that I've got more than 300 nm of "away from home waters" on this summer cruise I can safely say that I don't trust the charts that came pre-loaded in the Lowrance HDS-7, and my opinion is that they're "not fit for navigation". I saw place-mats in Charlie's summer home that are more accurate!

For example: This image is the area marking the main ship channel entering Buzzards Bay MA in the area between Cuttyhunk Island and Gooseberry Point. The official NOAA chart (updated) shows no rocks in the area near the cross-hairs, and the soundings of 6ft and 9ft are more like 63 or 78 ft, and the 5ft spot above those is probably the spot that reads 57 on the NOAA chart. The big ships are supposed to stay between these red and green buoys on the N-S channel. LOL!

Looks like I'm going to have to spring for the extra-cost Navionics chip.