I've used "open water" locators on hard water for years. I've been on a Lowrance m68c for awhile and love it for it's portability, resolution, screen options and (especially) the integrated GPS. I'ts perfect to have the locator/GPS on the boat and mark spots that I can walk/drive to on hard water. Never be w/o GPS again.
Now.... I just bought into a 1st gen 'Bird with side/down imaging. It's not as portable (it's an 8), but the prospect of side find/image on ice is intriguing and suits very much my open water excursions. I really wanted a 7 for better portability but the price was just too good to pass up.
That said, I had a Lowrance HDS 5 I was going to use. Had it all set and ready to roll but the side deal changed everything.....
Short answer: Yes. It will work very well and you will likely never look back.