It's not a bad set by all means, Hitachi makes a solid product that looks good. IMO, though, Hitachi plasmas REALLY need a professional ISF calibration to get even semi-accurate colors. Out of the box, at least from what I've seen, colors are extremely saturated (to the point where grass looks neon green), and is hard to fix just by user settings.
If you go with this set, I'd seriously suggest getting it calibrated. It runs between $300 to $400. I would also make sure that a pedestal/stand is included, if necessary. A lot of Hitachi sets, especially their 55" models, do not include stands, and cost anywhere from $200 to $400 for one.
For the best quality, I'd check out Pioneer, which HHGregg doesn't carry. They do carry Panny and Samsung, and their 1080p plasmas are both fantastic. A little more expensive, and only come in 50", so a little smaller, but will give you a better picture, IMO.
I have not personally seen that Hitachi plasma, but I have seen the 55" Director Series of last year extensively, as well as their new 50" 1080i models, and I wasn't very impressed, especially compared to the competition. The price is nice though, and a good calibration should significantly improve the picture.