summitman,
I just bought the SkyCaddy SG2.5, by SkyGolf. It works great, as I golf more than one state I took the option to download any course in the US. The yearly cost for that option is $49.50 per year. We are in Mesquite NV now and I downloaded the 6 courses here in less than 10 minutes. It stores up to 10 courses. Then on your computer through SkyGolf you have a inventory of your downloaded courses. As changes are made to any of those courses they are updated. Each hole also shows all water, sand traps and such, with the distance from your shot. Hope this helps.....