It's still hard, but improvements are big. ESPECIALLY co-op!
This time, precisely 10 years after the GUILT outbreak, a new virus has arrived, and this one is called Stigma. No acronyms, no brouhaha, just Stigma. But still, alleviating it is more or less the same as killing GUILT, at least at first (via laser), but when it gets worse, hell breaks loose. No really, it's very hard. Even in the cases that don't involve the virus such as making skin grafts to cover burns. It's already mind-racking, and that's just in "Easy" mode. Then again, it's a quality that it (Atlus) didn't correct from its predecessors (even in the first DS version) and has probably become notorious for it. Despite that, everything that has changed is for the better.
For one, the presentation, which was lackluster in Second Opinion, gets a boost. Yes, the dialogue is still presented in non-motile, occasionally expressive anime/manga drawings but the backdrops have become more detailed and not to mention more. The 3D renderings of the human body have also improved as well, as they are smoother and more detailed as well.
Nothing has changed with the gameplay, which is good. And though there is a bit of medical drama that occurs between operations, you'll probably want to skip them anyway, as you'll want to proceed with the operation instantly. It will be hard to get a high rating though, so don't be surprised if you get constant C's. One new mode is the challenge mode wherein the game challenges you to treat as many patients as you can in 5 minutes without the nurse guiding you. Plus. the game also benefits and gets easier from its new Multiplayer mode which lets another doctor helm the Wiimote for guidance. And hopefully your friend won't be afraid of virtual blood. If he is, there's not much of the red stuff anyway which makes this a more accessible and social game.
There are still some sound effects and background music retained or remixed from its predecessors and they will sound familiar when they're blared. Other than that, there is also some forgettable new tunes. Another major improvement is the inclusion of solid voiceovers which helps enliven the text-based dialogue, and I mean every word of it. Unfortunately, the talent is wasted on a generic script, but it's not actually bad.
Now for the first time in the series do I see a lot of replay value especially due to its fun co-op. If you've been withholding the purchase of the franchise, get an appointment and release your inner surgeon. In fact, this is probably the best original effort from third-party publishers (in the Wii or DS) ever seen.