The Bauhaus worked the best. And OpenCPN uses them well on the Mac. But I'm also thinking of the future when we can orient Google Earth photos to a lat / long grid. Often it's not the bottom I'm as worried about as land masses. Even with Bauhaus, accurate land masses helped show where the bottom contours would / should be. Traveling E towards Colombia we found some errors; however, because the land masses were accurate we were able to eyeball our way through the water without touching the bottom and without a leadline. The water in some areas E of the main cruising ground isn't as clear either. Lots of rivers close to the islands. Our sounder was on however.

We did find a French boat that had a set of charts much more accurate then those I had for the Sapzurro / Colombian-Panama coast. Don't remember who put them out and wasn't to concerned as we were leaving that area behind for a long, long time.

Ciao