Ok, I just want to be sure I am thinking right. On a fishfinder, the watt output (RMS) is the important number as far as accuracy.....right? Does the resolution of the unit in conjunction with the RMS matter? For example, on a lot of models I've been looking at, the lower end units have higher RMS, but lower resolution where the next step up will have lower RMS with higher resolution. Would this mean the lower priced unit is actually the better one? Also, is an external GPS receiver really all that much of an advantage over internal...and why? I know, seems like a lot of questions. But I am looking for a combo GPS/FF and want to get the best for my money. I think I have decided to get a Humminbird because eventually I plan to add a SI and want something I can share memory cards between. But for now I need something good at a decent price for my console as the one I have has finally given up the ghost. It was a cheap HB that came with my boat and was pretty reliable, so I'm sure an upgrade will be even better. Help please!!!