Richard, So far, my observation is, there is nothing (yet) on the Mac side to quite match the richness-of-function that Navionics and Coastal Explorer have today on the Windows side. For Nav software, the Windows side is best-of-breed today. Unfortunately, that brings Windows with it, which is definitely not best-of-breed in the OS Space. But, Nav offerings on the Mac side are catching up, if slowly. I never got into Navionics because I didn't like the fact that I couldn't use vanilla NOAA charts. I maintain a minimal Vista system that runs as a VM on Parallels Desktop on my Mac. I use it to run CE, which I do like. On the Mac side, I have used MacENC, and find it kludgy. It is tediously complex if you have a library of saved routes, which I do. A relatively new player in the Nav space that is supported cross-platform is Polar Navy's Polar View. That one has promise. It uses standard NOAA charts, and it updates them semi-automatically. For route planning, it is almost as easy as CE. The companion Polar Com I struggle with. I works OK with my wired GOS, but it doesn't like my Bluetooth GPS. Price wise, CE on Windows is around $350-$400. I believe - but please verify for yourself - Nobletech is more than CE, retail. Polar View, by comparison, is $40 - $50. MacENC was $180, but I think Polar View is equivalent functionality at a far better price point. If you're going to upgrade from a very old system, all of these alternatives will do what you have today. Also consider upgrading from Win 98 to an iPad. Garmin Bluechart, Navionics and SEAiq all have fairly feature-rich iPad nav applications. They will quickly drag you into the complex and wonderful world of NMEA0183, NMEA2000 and Seatalk multiplexors, but they are a fast-growing, inexpensive and interesting secondary (*not* primary) emerging nav technology. There's more detail on computers, Macs themselves, tablets, 3G/4G and wi-fi, and more detail on Nav software, on my website/blog, in this article: http://gilwellbear.wordpress.com/category/boat-technical-topics/equipment-topics/computers-and-data/. Hope this is useful. Jim Peg and Jim Healy aboard Sanctuary Currently at Rock Creek, Pasadena, MD http://gilwellbear.wordpress.com Monk 36 Hull #132 MMSI #367042570 AGLCA #3767 MTOA #3436