"any experience with this for ice fishing? THis would be nice for not only ice fishing but for mounting on the kayak in the summer."
I bought the 67C a few years back. Same as the 68C less the GPS capability. Use it on the hard & open water. Love the versatility for the price which lured me to the product in the first place. In sonar mode (ice fishing) the unit has performmed beyond my expectations. Simple put - it marks fish at accurate depths. No problems with glare at all. One nice feature is the ability to change flasher color patterns to compensate for ambient light conditions. You can also easily adjust the display angle for your viewing pleasure to help combat those sunny days. Battery life is superb. If there was one thing to complain about it would be noise. The unit will pick up noise from other flashers. I've been able to determine through trial & error I have to stay 8' to 10' away from others fishing with flashers. Funny thing about the noise issue is the unit doesn't ALWAYS pick up noise from other flashers when the two units are sitting side by side. It seems older models have more of a negative impact than newer models (Vexs & Marcum).
Last but not least - I had concerns about exposing the unit to colder temps and how the LCD would respond. That concern was put to rest long ago. I've been on the ice (not a shanty) for 8 hours straight with temps in the single digits with no problems. Lowrance suggests NOT to use the product in temps below -4F in which I haven't.
My only regret is that I didn't cough up the extra $100 get the 68C instead of the 67C for the GPS capability. That would have been a really nice feature for fishing those spots on a spot.