www.macenc.com uses NOAA raster or
preferebly NOAA ENC (S57) charting ... best of all you can download all NOAA charts for free.
MacENC is written for macs and therefore needs no 'emulation/translator' to decode from WinDOZE dopey OS, etc.
MacENC also serves as a 'hub' for peripheral navigation and can be easily integrated to AIS, Radar, Masthead Wind instruments (need NEMA 083 decoder) for VMG calculation/optimization, depth, rpm, etc, etc. etc. Theres also a very active forum for other integrations, etc. -
http://macsailing.net/fbb/ which highlights MacENC and other Mac 'friendly' stuff.
You can download a 'trial'/demo to see if you like it - above website. I would also suggest that you use an independent 'hockey puck' GPS receiver and mount it on your coachroof, etc. rather than using a 'clunky' serial port connection to Garmin, etc. GPS, chartplotters, etc. A bluetooth enabled GPS is perhaps a better alternative to a 'hockey puck'. Someday Garmin and the other GPS manufacturers will realize that 'serial ports' on computers became obsolete about 10-12 years ago.
MacENC one of THE very best nav. programs on the market, and naturally it runs on a 'mac' .... so you get the best of all worlds.
Ive been using MacENC as my 'hub' for long distance cruising for about 7 years ... it is OUTSTAND5TANDING.