[gslpro]

On my helm, I have a built-in Standard Horizon with the Bizer Lake map chip. Top notch. I also use my Ipad with the Lake Winni App. I like using both of the GPS, especially at night, for the different zoom levels I like. So far, the Ipad app works great and has been accurate, but I think it will take several more trips before I ever truly trust it. But, it does have a real GPS chip in it, and it works pretty good. Also, it is nice to have the on-screen map look the same (exact same) as the laminated Bizer chart in my hand. I also have a garmin Zumo 550 motorcycle gps loaded with both the Garmin and Bizer maps. It is okay on both. The colors of the buoys is not red/black like they are supposed to be, which is the problem you will find in most car gps's. The Garmin map shows up black/white, but positioning is still accurate. I used this gps before I bought the Ipad so that I could use it at a different zoom, say for the Broads, but leave the built-in unit at a tighter zoom level for the accurate buoy location.

So, I guess it depends on what you will be doing with the GPSs that will decide on what you need. People like the Garmin $10 data map, but personally, I like the Bizer one, if not only to be the same as the chart, which is the number one source you should be using. GPS is only for assistance in navigation. Good luck.