if you must know, my st400o+ mkii went completely nuts and blew out my whole electrical system while sailing. the good news is that raymarine sent me a cheque to cover everything, but will not since communicate what went wrong, how to prevent a reoccurence in the future or any other question i have about the unit. on the other hand, garmin in support of my 3010C questions and software updates has been delightful; so have garhauer, seaward, duthcman, datamarine, catalina, and almost everybody else i have dealt with, so i'm not a crank who can't get along with people. go ahead and buy raymarine when the market has so many excellent alternatives, just don't say you weren't warned. by the way, beechcraft is owned by raytheon but the factory avionics of choice are garmin. think about that.