I've got a 43H70 at home and I have no complaints. It's a nice set.
Just make sure that ambient light isn't an issue in your sunroom (sure sounds like it might be!). I have a room full of windows with no real problems during the day, but I've removed the protective screen on my set which helped considerably.
Yes light is a problem, lots of windows, that is one reason I want the HX series. The screen is supposed to have better anti-glare characteristics than the H series.