I have the Lowrance iFinder H20 and I really like it.* I also have a Lowrance unit on the boat, so I can transfer the saved waypoints back and forth using MMC cards.* That's a huge benefit for me.* Structure I mark on my boat mounted unit I can quickly transfer to the handheld unit for ice fishing and vice versa.* Lowrance has a few free bottom contour maps for Colorado and Wyoming lakes, too, including some that I fish a lot (http://www.lowrance.com/Mapping/LakeMaps/index.asp
).* The Lowrance units accept the Navionics maps and charts, too.
It largely depends on personal preference.* I've used Lowrance sonars with good results for years, so when it came time to get a combo sonar/GPS unit for the boat that made the choice pretty easy for me.* And it didn't make sense to get handheld that was incompatible with what I had on the boat.* So both are Lowrance.