I asked Jerry this a couple of months ago. He recommended the garmin 76. At crappie camp, darryl morris had this unit also. I wound up going with the lowrance h20c. (color) The lowrance h20 (b&W)has a lot of good features on it also at a comparable price. either one of those will work good. the 12 volt adapter comes with it also, which is something you have to buy extra on the garmin 76.
The only problem with most of the gps units is that they don't come with high detail maps, & you will have to buy them separately. Lowrance has a lot of free lake maps, & if you are fishing any of those lakes, it is very good. there are a couple from MS, but not a lot. I think the h20 has a slightly larger screenthan the garmin 76. I wound up getting the ram mount to put it on my boat, & had a buddy w/ a lowrance map software, & he made me a card (they use sd cards for addl. info), so it is set up exactly the way i want it.
In addition, @ crappie camp on greeson, the waypoints that jerry & darryl posted were dead on. I found every brushpile that I looked for, & they were right where the points said they were. hope this helps.