I have the 176 that you linked to. I have the black and white though. The sales guy told me don't bother with the color on that model, to hard to read in the sunlight. He said if you really want color spend the $ on the higher end ones and they are great. You just have to pay for good color.
Buy the biggest one that you can afford and fit on the dash black and white or color. Mine is near impossible to read while under way, a great unit just to small.