I've got the SI GPS and it seems do most of the functions of the expensive units. The only negative is the small screen. The great big positive is the price. It is very important to have it properly set up or tuned and there is nobody better to do that than Slade Daugherty. He is the best just check out this site. He set up my unit and he can give you advice based on what you want. I like mine and would recommend. I also recommend you add the Lakemaster Maps.