MAP 76 OR 76S ?
i'd say if you plan on using bluecharts get the s. if not get the 76. the compas and altimeter seem like novilty items on the s unit.
i'm no expert on this topic, but i have to believe the altimeter function can't be very accurate unless there's a way for you to set the "sea level" barameteric pressure somewhere in the unit. otherwise it would show change in altitude just from the normal changes in ouside barametric pressure. i'm very curious to hear from someone who has experience with this.
the compas feature could be accurate, but i would definately want to cary a spare.
thom, let me know how well your's works.
chris l.