This spring I put a Hook 5 on my boat's console and a Hook 7 up in the bow where I fish, and I like them both. I would suggest you spend a little extra for the mapping chip as it will give you a full blown GPS with topographic contours. I have it on my console model but not on the bigger unit in the bow as I do not use the GPS up there. The one thing you need to remember with any of these Lowrance Hook series finders is to set them in the proper mode. Do not use the general purpose mode as it's good for nothing. Use the freshwater mode for smallmouth fishing in water no deeper than 35 or so feet. If you are striper fishing over deeper water than the deep water mode is best.
One thing to remember with modern depth finders is they are far better than comparable models of just five or six years ago. That $300 Hook 7 is a much superior finder than finder that cost $300 10 years ago. While the more expensive finders have more capability, you have to ask yourself how much capability do you really need to fish a freshwater lake like Powell? The ultra expensive finders that you see on the newer high performance bass boats have far more capability than most anglers are willing to learn how to use, and it's questionable if all that added capability will actually help one catch more fish. You sort of have to do a cost/benefit analysis. To answer your question as best I can, $300 is a very good price for a Hook 7 unit, and whether it is a good model or not in your eyes will depend largely on the unit you're replacing. I can tell you my Hook depth finders are a major improvement on the on the 10 and 13-year-old units they replaced.
Ed Gerdemann